Sunday, December 13, 2009

Function overloading

Thus, the name abs represents the general action which is being
performed. It is left to the compiler to choose the right specific version for a particular
circumstance. You, the programmer, need only remember the general operation being
performed. Through the application of polymorphism, several names have been
reduced to one.

Saturday, December 12, 2009

c program without main

http://c4learn.com/c-programs/c-program-without-main-function.html

Thursday, December 10, 2009

Some basic networking interview questions

1. What are 10Base2, 10Base5 and 10BaseT Ethernet LANs
10Base2—An Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses
baseband
signaling, with a contiguous cable segment length of 100
meters and a maximum of 2 segments.
10Base5—An Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses
baseband
signaling, with 5 continuous segments not exceeding 100
meters per segment.
10BaseT—An Ethernet term meaning a maximum transfer rate of 10 Megabits per second that uses
baseband
signaling and twisted pair cabling.
2. Explain the difference between an unspecified passive open and a fully specified passive open
An unspecified passive open has the server waiting for a connection request from a client. A fully
specified passive
open has the server waiting for a connection from a
specific client.
3. Explain the function of Transmission Control Block
A TCB is a complex data structure that contains a considerable amount of information about each
connection.
4. Explain a Management Information Base (MIB)
A Management Information Base is part of every SNMP-managed device. Each SNMP agent has the
MIB database that
contains information about the device's status, its
performance, connections, and configuration. The MIB is queried by SNMP.
5. Explain anonymous FTP and why would you use it
Anonymous FTP enables users to connect to a host without using a valid login and password. Usually,
anonymous FTP
uses a login called anonymous or guest, with the
password usually requesting the user's ID for tracking purposes only. Anonymous FTP is used to
enable a large number
of users to access files on the host without having
to go to the trouble of setting up logins for them all. Anonymous FTP systems usually have strict
controls over the areas
an anonymous user can access.
6. Explain a pseudo tty
A pseudo tty or false terminal enables external machines to connect through Telnet or rlogin. Without
a pseudo tty, no
connection can take place.
7. Explain REX
What advantage does REX offer other similar utilities
8. What does the Mount protocol do
The Mount protocol returns a file handle and the name of the file system in which a requested file
resides. The message
is sent to the client from the server after reception
of a client's request.
9. Explain External Data Representation
External Data Representation is a method of encoding data within an RPC message, used to ensure
that the data is not
system-dependent.
10. Explain the Network Time Protocol ?
11. BOOTP helps a diskless workstation boot. How does it get a message to the network looking for
its IP address and the location of its operating system boot files
BOOTP sends a UDP message with a subnetwork broadcast address and waits for a reply from a
server that gives it the IP address. The same message might contain the name of the machine that has
the boot files on it. If the boot image location is not specified, the workstation sends another UDP
message to query the server.
12. Explain a DNS resource record
A resource record is an entry in a name server's database. There are several types of resource records
used, including name-to-address resolution information. Resource records are maintained as ASCII
files.
13. What protocol is used by DNS name servers
DNS uses UDP for communication between servers. It is a better choice than TCP because of the
improved speed a connectionless protocol offers. Of course, transmission reliability suffers with UDP.
14. Explain the difference between interior and exterior neighbor gateways
Interior gateways connect LANs of one organization, whereas exterior gateways connect the
organization to the outside world.
15. Explain the HELLO protocol used for
The HELLO protocol uses time instead of distance to determine optimal routing. It is an alternative to
the Routing Information Protocol.
16. What are the advantages and disadvantages of the three types of routing tables
The three types of routing tables are fixed, dynamic, and fixed central. The fixed table must be
manually modified every time there is a change. A dynamic table changes its information based on
network traffic, reducing the amount of manual maintenance. A fixed central table lets a manager
modify only one table, which is then read by other devices. The fixed central table reduces the need to
update each machine's table, as with the fixed table. Usually a dynamic table causes the fewest
problems for a network
administrator, although the table's contents can change without the administrator being aware of the
change.
17. Explain a TCP connection table
18. Explain source route
It is a sequence of IP addresses identifying the route a datagram must follow. A source route may
optionally be included in an IP datagram header.
19. Explain RIP (Routing Information Protocol)
It is a simple protocol used to exchange information between the routers.
20. Explain SLIP (Serial Line Interface Protocol)
It is a very simple protocol used for transmission of IP datagrams across a serial line.
21. Explain Proxy ARP
It is using a router to answer ARP requests. This will be done when the originating host believes that a
destination is local, when in fact is lies beyond router.
22. Explain OSPF
It is an Internet routing protocol that scales well, can route traffic along multiple paths, and uses
knowledge of an Internet's topology to make accurate routing decisions.
23. Explain Kerberos
It is an authentication service developed at the Massachusetts Institute of Technology. Kerberos uses
encryption to prevent intruders from discovering passwords and gaining unauthorized access to files.
24. Explain a Multi-homed Host
It is a host that has a multiple network interfaces and that requires multiple IP addresses is called as a
Multi-homed Host.
25. Explain NVT (Network Virtual Terminal)
It is a set of rules defining a very simple virtual terminal interaction. The NVT is used in the start of a
Telnet session.
26. Explain Gateway-to-Gateway protocol
It is a protocol formerly used to exchange routing information between Internet core routers.
27. Explain BGP (Border Gateway Protocol)
It is a protocol used to advertise the set of networks that can be reached with in an autonomous
system. BGP enables this information to be shared with the autonomous system. This is newer than
EGP (Exterior Gateway Protocol).
28. Explain autonomous system
It is a collection of routers under the control of a single administrative authority and that uses a
common Interior Gateway Protocol.
29. Explain EGP (Exterior Gateway Protocol)
It is the protocol the routers in neighboring autonomous systems use to identify the set of networks
that can be reached
within or via each autonomous system.
30. Explain IGP (Interior Gateway Protocol)
It is any routing protocol used within an autonomous system.
31. Explain Mail Gateway
It is a system that performs a protocol translation between different electronic mail delivery protocols.
32. Explain wide-mouth frog
Wide-mouth frog is the simplest known key distribution center (KDC) authentication protocol.
33. What are Digrams and Trigrams
The most common two letter combinations are called as digrams. e.g. th, in, er, re and an. The most
common three letter combinations are called as trigrams. e.g. the, ing, and, and ion.
34. Explain silly window syndrome
It is a problem that can ruin TCP performance. This problem occurs when data are passed to the
sending TCP entity in large blocks, but an interactive application on the receiving side reads 1 byte at
a time.
35. Explain region
When hierarchical routing is used, the routers are divided into what we call regions, with each router
knowing all the details about how to route packets to destinations within its own region, but knowing
nothing about the internal structure of other regions.
36. Explain multicast routing
Sending a message to a group is called multicasting, and its routing algorithm is called multicast
routing.
37. Explain traffic shaping
One of the main causes of congestion is that traffic is often busy. If hosts could be made to transmit at
a uniform rate, congestion would be less common. Another open loop method to help manage
congestion is forcing the packet to be transmitted at a more predictable rate. This is called traffic
shaping.
38. Explain packet filter
Packet filter is a standard router equipped with some extra functionality. The extra functionality allows
every incoming or outgoing packet to be inspected. Packets meeting some criterion are forwarded
normally. Those that fail the test are dropped.
39. Explain virtual path
Along any transmission path from a given source to a given destination, a group of virtual circuits can
be grouped together into what is called path.
40. Explain virtual channel
Virtual channel is normally a connection from one source to one destination, although multicast
connections are also permitted. The other name for virtual channel is virtual circuit.
41. Explain logical link control
One of two sublayers of the data link layer of OSI reference model, as defined by the IEEE 802
standard. This sublayer is responsible for maintaining the link between computers when they are
sending data across the physical network connection.
42. Why should you care about the OSI Reference Model
It provides a framework for discussing network operations and design.
43. Explain the difference between routable and non- routable protocols
Routable protocols can work with a router and can be used to build large networks. Non-Routable
protocols are designed to work on small, local networks and cannot be used with a router
44. Explain MAU
In token Ring , hub is called Multistation Access Unit(MAU).
45. Explain 5-4-3 rule
In a Ethernet network, between any two points on the network, there can be no more than five network
segments or four repeaters, and of those five segments only three of segments can be populated.
46. Explain the difference between TFTP and FTP application layer protocols
The Trivial File Transfer Protocol (TFTP) allows a local host to obtain files from a remote host but
does not provide reliability or security. It uses the fundamental packet delivery services offered by
UDP.
The File Transfer Protocol (FTP) is the standard mechanism provided by TCP / IP for copying a file
from one host to another. It uses the services offered by TCP and so is reliable and secure. It
establishes two connections (virtual circuits) between the hosts, one for data transfer and another for
control information.
47. Explain the range of addresses in the classes of internet addresses
Class A 0.0.0.0 - 127.255.255.255
Class B 128.0.0.0 - 191.255.255.255
Class C 192.0.0.0 - 223.255.255.255
Class D 224.0.0.0 - 239.255.255.255
Class E 240.0.0.0 - 247.255.255.255
48. Explain the minimum and maximum length of the header in the TCP segment and IP datagram
The header should have a minimum length of 20 bytes and can have a maximum length of 60 bytes.
49. Explain difference between ARP and RARP
The address resolution protocol (ARP) is used to associate the 32 bit IP address with the 48 bit
physical address, used by a host or a router to find the physical address of another host on its network
by sending a ARP query packet that includes the IP address of the receiver. The reverse address
resolution protocol (RARP) allows a host to discover its Internet address when it knows only its
physical address.
50. Explain ICMP
ICMP is Internet Control Message Protocol, a network layer protocol of the TCP/IP suite used by
hosts and gateways to send notification of datagram problems back to the sender. It uses the echo test /
reply to test whether a destination is reachable and responding. It also handles both control and error
messages.
51. What are the data units at different layers of the TCP / IP protocol suite
The data unit created at the application layer is called a message, at the transport layer the data unit
created is called either a segment or an user datagram, at the network layer the data unit created is
called the datagram, at the data link layer the datagram is encapsulated in to a frame and
finally transmitted as signals along the transmission media.
52. Explain Project 802
It is a project started by IEEE to set standards that enable intercommunication between equipment
from a variety of manufacturers. It is a way for specifying functions of the physical layer, the data link
layer and to some extent the network layer to allow for interconnectivity of major LAN protocols.
It consists of the following:
802.1 is an internetworking standard for compatibility of different LANs and MANs across protocols.
802.2 Logical link control (LLC) is the upper sublayer of the data link layer which is non-architecturespecific,
that is remains the same for all IEEE-defined LANs.
Media access control (MAC) is the lower sublayer of the data link layer that contains some distinct
modules each carrying proprietary information specific to the LAN product being used. The modules
are Ethernet LAN (802.3), Token ring LAN (802.4), Token bus LAN (802.5).
802.6 is distributed queue dual bus (DQDB) designed to be used in MANs.
53. Explain Bandwidth
Every line has an upper limit and a lower limit on the frequency of signals it can carry. This limited
range is called the bandwidth.
54. Difference between bit rate and baud rate.
Bit rate is the number of bits transmitted during one second whereas baud rate refers to the number of
signal units per second that are required to represent those bits. baud rate = bit rate / N where N is noof-
bits represented by each signal shift.
55. Explain MAC address
The address for a device as it is identified at the Media Access Control (MAC) layer in the network
architecture. MAC address is usually stored in ROM on the network adapter card and is unique.
56. Explain attenuation
The degeneration of a signal over distance on a network cable is called attenuation.
57. Explain cladding
A layer of a glass surrounding the center fiber of glass inside a fiber-optic cable.
58. Explain RAID
A method for providing fault tolerance by using multiple hard disk drives.
59. Explain NETBIOS and NETBEUI
NETBIOS is a programming interface that allows I/O requests to be sent to and received from a
remote computer and it hides the networking hardware from applications. NETBEUI is NetBIOS
extended user interface. A transport protocol designed by microsoft and IBM for the use on small
subnets.
60. Explain redirector
Redirector is software that intercepts file or prints I/O requests and translates them into network
requests. This comes under presentation layer.
61. Explain Beaconing
The process that allows a network to self-repair networks problems. The stations on the network
notify the other stations on the ring when they are not receiving the transmissions. Beaconing is used
in Token ring and FDDI networks.
62. Explain terminal emulation, in which layer it comes
Telnet is also called as terminal emulation. It belongs to application layer.
63. Explain frame relay, in which layer it comes
Frame relay is a packet switching technology. It will operate in the data link layer.
64. What do you meant by "triple X" in Networks
The function of PAD (Packet Assembler Disassembler) is described in a document known as X.3. The
standard protocol has been defined between the terminal and the PAD, called X.28; another standard
protocol exists between hte PAD and the network, called X.29. Together, these three recommendations
are often called "triple X"
65. Explain SAP
Series of interface points that allow other computers to communicate with the other layers of network
protocol stack.
66. Explain subnet
A generic term for section of a large networks usually separated by a bridge or router.
67. Explain Brouter
Hybrid devices that combine the features of both bridges and routers.
68. How Gateway is different from Routers
A gateway operates at the upper levels of the OSI model and translates information between two
completely different network architectures or data formats.
69. What are the different type of networking / internetworking devices
Repeater: Also called a regenerator, it is an electronic device that operates only at physical layer. It
receives the signal in the network before it becomes weak, regenerates the original bit pattern and puts
the refreshed copy back in to the link.
Bridges: These operate both in the physical and data link layers of LANs of same type. They divide a
larger network in to smaller segments. They contain logic that allow them to keep the traffic for each
segment separate and thus are repeaters that relay a frame only the side of the segment containing the
intended recipent and control congestion.
Routers: They relay packets among multiple interconnected networks (i.e. LANs of different type).
They operate in the physical, data link and network layers. They contain software that enable them to
determine which of the several possible paths is the best for a particular transmission.
Gateways:
They relay packets among networks that have different protocols (e.g. between a LAN and a WAN).
They accept a packet formatted for one protocol and convert it to a packet formatted for another
protocol before forwarding it. They operate in all seven layers of the OSI model.
70. Explain mesh network
A network in which there are multiple network links between computers to provide multiple paths for
data to travel.
71. Explain passive topology
When the computers on the network simply listen and receive the signal, they are referred to as
passive because they don’t amplify the signal in any way. Example for passive topology - linear bus.
72. What are the important topologies for networks
BUS topology:
In this each computer is directly connected to primary network cable in a single line.
Advantages:
Inexpensive, easy to install, simple to understand, easy to extend.
STAR topology:
In this all computers are connected using a central hub.
Advantages:
Can be inexpensive, easy to install and reconfigure and easy to trouble shoot physical problems.
RING topology:
In this all computers are connected in loop.
Advantages:
All computers have equal access to network media, installation can be simple, and signal does not
degrade as much as
in other topologies because each computer
regenerates it.
73. What are major types of networks and explain
Server-based network
Peer-to-peer network
Peer-to-peer network, computers can act as both servers sharing resources and as clients using the
resources.
Server-based networks provide centralized control of network resources and rely on server computers
to provide security and network administration
74. Explain Protocol Data Unit
The data unit in the LLC level is called the protocol data unit (PDU). The PDU contains of four fields
a destination service access point (DSAP), a source service access point (SSAP), a control field and an
information field. DSAP, SSAP are addresses used by the LLC to identify the protocol stacks on the
receiving and sending machines that are generating and using the data. The control field specifies
whether the PDU frame is a information frame (I - frame) or a supervisory frame (S - frame) or a
unnumbered frame (U - frame).
75. Explain difference between baseband and broadband transmission
In a baseband transmission, the entire bandwidth of the cable is consumed by a single signal. In
broadband transmission, signals are sent on multiple frequencies, allowing multiple signals to be sent
simultaneously.
76. What are the possible ways of data exchange
(i) Simplex (ii) Half-duplex (iii) Full-duplex.
77. What are the types of Transmission media
Signals are usually transmitted over some transmission media that are broadly classified in to two
categories.
Guided Media:
These are those that provide a conduit from one device to another that include twisted-pair, coaxial
cable and fiber-optic cable. A signal traveling along any of these media is directed and is contained by
the physical limits of the medium. Twisted-pair and coaxial cable use metallic that accept
and transport signals in the form of electrical current. Optical fiber is a glass or plastic cable that
accepts and transports signals in the form of light.
Unguided Media:
This is the wireless media that transport electromagnetic waves without using a physical conductor.
Signals are broadcast either through air. This is done through radio communication, satellite
communication and cellular telephony.
78. Explain point-to-point protocol
A communications protocol used to connect computers to remote networking services including
Internet service providers.
79. What are the two types of transmission technology available
(i) Broadcast and (ii) point-to-point
80. Difference between the communication and transmission.
Transmission is a physical movement of information and concern issues like bit polarity,
synchronization, clock etc. Communication means the meaning full exchange of information between
two communication media.

Wednesday, December 9, 2009

Basic Interview Questions on networking

What is DHCP?

DHCP stands for Dynamic Host Configuration Technology. The basic purpose of the DHCP is to assign the IP addresses and the other network configuration such as DNS, Gateway and other network settings to the client computers. DHCP reduces the administrative task of manually assigning the IP addresses to the large number of the computers in a network.

What is DNS and how it works?

DNS stands for Domain name system and it translates (converts) the host name into the IP address and IP address into to the host name. Every domain and the computer on the internet is assigned a unique IP address. The communication on the internet and in the network is based on the IP addresses. IP addresses are in this format 10.1.1.100, 220.12.1.22.3, 1.1.1.1 etc. IP addresses can’t be remembered but the host names (e.g. www.networktutorials.info, xyz.com, abc.com) are easy to remember instead of their IP addresses.

What is a Firewall?

Firewall is a protective boundary for a network and it prevents the unauthorized access to a network. Most of the Windows operating system such as Windows XP Professional has built-in firewall utilities. There are the large number of the third party firewall software and the basic purpose of all the firewall software and hardware is same i.e. to block the unauthorized user access to a network.

What is WAN?

WAN stands for wide area network and it covers the broader geographical area. Basically there are three types of a computer network LAN (Local Area Network), MAN (Metropolitan Area Network) and WAN (Wide Area Network). The communication in a WAN is based on the Routers. A WAN network can cover a city, country or continents.

Define VOIP Communication Technology

VOIP stands for Voice over IP and this technology is used for transmitted the voice over the IP based long distance network to make phone calls. VOIP phone calls are very cheap and a large number of the corporate offices and home users are using VOIP technology
to make long distance phone calls.

What is Wi Max Technology?

Wi Max is a wireless broadband technology and it is a advance shape of the Wi Fi (which was a base band technology). Wi Max supports data, video and audio communication at the same time at a very high speed up to 70 Mbps.

Define Network Gateway

Network Gateway can be software or a hardware. A gateway is usually a joining point in a network i.e. it connects two networks. A computer with two LAN cards can act as a gateway.

What is a Router?

A router routes the traffic to its destination based on the source and destination IP addresses, which are placed in the routing software known as routing table.

How Fiber Optic Cable Works

Fiber optics provides the fastest communication medium for data and voice. Data can travel at the speed of light through the fiber optic cables. ISPs and corporate offices are usually connected with each other with the fiber optic cables to provide high speed connectivity.

What is File Server?

A file server is a computer in a network that authenticates the user access in a network such as Windows 2000/2003 Servers.

Define Seven Layers of OSI Model

There are seven layers of the OSI model. The basic purpose of these layers is to understand the communication system and data transmission steps. The seven layers are Application, Presentation, Session, Transport, Network, Data Link and Physical. You can remember the name of these layers by this phrase. “All people seems to need data processing”.

Define GSM Technology

GSM is a short range wireless technology and is usually used in the mobile phones, hand help devices, MP3 players, Laptops, computers and in cars.

Various Software model

Software Process is a particular method, generally involving a number of steps along with ordering constraints on execution, to produce software with desired outcome


2 Major processes : Development, Project Management.


Methodologies for Software Development - ETVX 


ETVX model
(l.w. = ex , tv...entry, exit; task validation)



Quality in the process

A quality process has the right inputs and performs the right actions to produce outputs that meet the needs of customer processes.
Definitions of quality thus include:
  • Fitness for purpose
  • Right output, right time, right place
  • Customer satisfaction

ETVX Points

There are four places where the quality can be specified and checked:
  • Entry criteria define what inputs are required and what quality these must be to achieve the exit criteria. Entry criteria should be communicated to supplier processes, to become their exit criteria. If supplier processes are sufficiently well controlled, then there is no need to check inputs.
  • Task definitions specify the actions within the process.
  • Validation definitions identify test points within the process and define the tests and criteria for checking at these points. This enables problems to be caught close to their cause, reducing rework and scrap costs, and enabling problem causes to be addressed.
  • Exit criteria define what outputs are required and what quality these must be to meet the needs of customer processes. Exit criteria may be derived from the entry criteria of customer processes.


Common Process models - , Waterfall model, Prototype, spiral

SDLC - software development life cycle

Waterfall model 
Feasibility report / Requirement Analysis,
System Design, Implementation/Coding, Testing , Deployment, Maintenance
FDC TDM
(Fools Dont cost, Tools Dont make)


nLinear ordering implies each phase should have some output
nThe output must be validated/certified
nOutputs of earlier phases: work products
nCommon outputs of a waterfall: SRS, project plan, design docs, test plan and reports, final code, supporting docs




Prototyping Model
PrototypingSoftware prototyping, an activity during certain software development, is the creation of prototypes, i.e., incomplete versions of the software program being developed.
A prototype typically simulates only a few aspects of the features of the eventual program, and may be completely different from the eventual implementation.








Software management process

Capability Maturity Model

(H A R D M O DEL

Level 1 - Ad hoc (Chaotic)
It is characteristic of processes at this level that they are (typically) undocumented and in a state of dynamic change, tending to be driven in an ad hoc, uncontrolled and reactive manner by users or events. This provides a chaotic or unstable environment for the processes.
Level 2 - Repeatable
It is characteristic of processes at this level that some processes are repeatable, possibly with consistent results. Process discipline is unlikely to be rigorous, but where it exists it may help to ensure that existing processes are maintained during times of stress.
Level 3 - Defined
It is characteristic of processes at this level that there are sets of defined and documented standard processes established and subject to some degree of improvement over time. These standard processes are in place (i.e., they are the AS-IS processes) and used to establish consistency of process performance across the organization.
Level 4 - Managed
It is characteristic of processes at this level that, using process metrics, management can effectively control the AS-IS process (e.g., for software development ). In particular, management can identify ways to adjust and adapt the process to particular projects without measurable losses of quality or deviations from specifications. Process Capability is established from this level.
Level 5 - Optimized
It is a characteristic of processes at this level that the focus is on continually improving process performance through both incremental and innovative technological changes/improvements.

Tuesday, December 8, 2009

Left most n digits divisible by n

A number of 9 digits has the following properties:


  • The number comprising the leftmost two digits is divisible by 2, that comprising the leftmost three digits is divisible by 3, the leftmost four by 4, the leftmost five by 5, and so on for the nine digits of the number i.e. the number formed from the first n digits is divisible by n, 2<=n<=9.

  • Each digit in the number is different i.e. no digits are repeated.
  • The digit 0 does not occur in the number i.e. it is comprised only of the digits 1-9 in some order.
Find the number.

Answer
The answer is 381654729 One way to solve it is Trial-&-Error. You can make it bit easier as odd positions will always occupy ODD numbers and even positions will always occupy EVEN numbers. Further 5th position will contain 5 as 0 does not occur.
At odd points we have  3 1 5 7 9
At even points we have 8 6 4 2

Aptitude Quesions and answers

1.One of the following is my secret word:AIM  DUE  MOD  OAT  TIE.With the list in front of you, if I were to tell you any one of my secret word, then you would be able to tell me the number of vowels in my secret word.Which is my secret word?
Ans.TIE

2.In the following figure:A  B  C
                                              D
                                              E   F  G
                                                       H
                                                       I
Each of the digits 1, 2, 3, 4, 5, 6, 7, 8, and 9 is:
a)Represented by a different letter in the figure above.
b)Positioned in the figure above so that each of A + B + C,C + D +E,E + F + G, and G + H + I is equal to 13.
Which digit does E represent?

Ans.E is 4

3.One of Mr. Horton,his wife,their son,and Mr. Horton's mother is a doctor and another is a lawyer.
a)If the doctor is younger than the lawyer, then the doctor and the lawyer are not blood relatives.
b)If the doctor is a woman, then the doctor and the lawyer are blood relatives.
c)If the lawyer is a man, then the doctor is a man.
Whose occupation you know?

Ans.Mr. Horton:he is the doctor.

4.Here is a picture of two cubes:
                                               


         
  a)The two cubes are exactly alike.
  b)The hidden faces indicated by the dots have the same alphabet on them.
Which alphabet-q, r, w, or k is on the faces indicated by the dots?

Ans.q



5.In the following figure:
                                    A              D
                                    B      G     E
                                    C             F

Each of the seven digits from 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9 is:
  a)Represented by a different letter in the figure above.
  b)Positioned in the figure above so that A*B*C,B*G*E, and D*E*F are equal.
Which digit does G represent?

Ans.G represents the digit 2.

6.Mr. and Mrs. Aye and Mr. and Mrs. Bee competed in a chess tournament.Of the three games played:
  a)In only the first game werethe two players married to each other.
  b)The men won two games and the women won one game.
  c)The Ayes won more games than the Bees.
  d)Anyone who lost game did not play the subsequent game.
Who did not lose a game?

Ans.Mrs.Bee did not lose a game.

7.Three piles of chips--pile I consists one chip, pile II consists of chips, and pile III consists of three chips--are to be used in game played by Anita and Brinda.The game requires:
  a)That each player in turn take only one chip or all chips from just one pile.
  b)That the player who has to take the last chip loses.
  c)That Anita now have her turn.
From which pile should Anita draw in order to win?

Ans.Pile II

8.Of Abdul, Binoy, and Chandini:
  a)Each member belongs to the Tee family whose members always tell the truth or to the El family whose members        always lie.
  b)Abdul says ''Either I belong or Binoy belongs to a different family from the other two."
     Whose family do you name of?

Ans.Binoy's family--El.
9.In a class composed of x girls and y boys what part of the class is composed of girls

A.y/(x + y)
B.x/xy
C.x/(x + y)
D.y/xy

Ans.C


10.What is the maximum number of half-pint bottles of cream that can be filled with a 4-gallon can of cream(2 pt.=1 qt. and 4 qt.=1 gal)

A.16
B.24
C.30
D.64

Ans.D


11.If the operation,^ is defined by the equation x ^ y = 2x + y,what is the value of a in 2 ^ a = a ^ 3

A.0
B.1
C.-1
D.4

Ans.B


12.A coffee shop blends 2 kinds of coffee,putting in 2 parts of a 33p. a gm. grade to 1 part of a 24p. a gm.If the mixture is changed to 1 part of the 33p. a gm. to 2 parts of the less expensive grade,how much will the shop save in blending 100 gms.

A.Rs.90
B.Rs.1.00
C.Rs.3.00
D.Rs.8.00

Ans.C


13.There are 200 questions on a 3 hr examination.Among these questions are 50 mathematics problems.It is suggested that twice as much time be spent on each maths problem as for each other question.How many minutes should be spent on mathematics problems

A.36
B.72
C.60
D.100

Ans.B






14.In a group of 15,7 have studied Latin, 8 have studied Greek, and 3 have not studied either.How many of these studied both Latin and Greek

A.0
B.3
C.4
D.5

Ans.B


15.If 13 = 13w/(1-w) ,then (2w)2 =

A.1/4
B.1/2
C.1
D.2

Ans.C


16. If a and b are positive integers and (a-b)/3.5 = 4/7, then

(A) b < a
(B) b > a
(C) b = a
(D) b >= a

Ans. A


17. In june a baseball team that played 60 games had won 30% of its game played. After a phenomenal winning streak this team raised its average to 50% .How many games must the team have won in a row to attain this average?

A. 12
B. 20
C. 24
D. 30

Ans. C


18. M men agree to purchase a gift for Rs. D. If three men drop out how much more will each have to contribute towards the purchase of the gift/

A. D/(M-3)
B. MD/3
C. M/(D-3)
D. 3D/(M2-3M)

Ans. D


19. A company contracts to paint 3 houses. Mr.Brown can paint a house in 6 days while Mr.Black would take 8 days and Mr.Blue 12 days. After 8 days Mr.Brown goes on vacation and Mr. Black begins to work for a period of 6 days. How many days will it take Mr.Blue to complete the contract?

A. 7
B. 8
C. 11
D. 12

Ans.C


20. 2 hours after a freight train leaves Delhi a passenger train leaves the same station travelling in the same direction at an average speed of 16 km/hr. After travelling 4 hrs the passenger train overtakes the freight train. The average speed of the freight train was?

A. 30
B. 40
C.58
D. 60

Ans. B

21. If 9x-3y=12 and 3x-5y=7 then 6x-2y = ?

A.-5
B. 4
C. 2
D. 8

Ans. D
22. There are 5 red shoes, 4 green shoes. If one draw randomly a shoe what is the probability of getting a red shoe

Ans 5c1/ 9c1


23. What is the selling price of a car? If the cost of the car is Rs.60 and a  profit of 10% over selling price is earned

Ans: Rs 66/-




24. 1/3 of girls , 1/2 of boys go to canteen .What factor and total number of classmates go to canteen.

Ans: Cannot be determined.


25. The price of a product is reduced by 30% . By what percentage should it be increased to make it 100%

Ans: 42.857%


26. There is a square of side 6cm . A circle is inscribed inside the square. Find the ratio of the area of circle to square.

Ans. 11/14
27. There are two candles of equal lengths and of different thickness. The thicker one lasts of six hours. The thinner 2 hours less than the thicker one. Ramesh lights the two candles at the same time. When he went to bed he saw the thicker one is twice the length of the thinner one. How long ago did Ramesh light the two candles .

Ans: 3 hours.

28. If M/N = 6/5,then 3M+2N = ?
29. If p/q = 5/4 , then 2p+q= ?
30. If PQRST is a parallelogram what it the ratio of triangle PQS & parallelogram PQRST .
Ans: 1:2
31. The cost of an item is Rs 12.60. If the profit is 10% over selling price what is the selling price ?
Ans: Rs 13.86/-
32. There are 6 red shoes & 4 green shoes . If two of red shoes are drawn what is the probability of getting red shoes
Ans: 6c2/10c2
33. To 15 lts of water containing 20% alcohol, we add 5 lts of pure water. What is % alcohol.
Ans : 15%
34. A worker is paid Rs.20/- for a full days work. He works 1,1/3,2/3,1/8.3/4 days in a week. What is the total amount paid for that worker ?
Ans : 57.50
35. If the value of x lies between 0 & 1 which of the following is the largest?
(a) x
(b) x2
(c) -x
(d) 1/x

Ans : (d)

 36. If the total distance of a journey is 120 km .If one goes by 60 kmph and comes back at 40kmph what is the average speed during the journey? 
Ans: 48kmph
37. A school has 30% students from Maharashtra .Out of these 20% are Bombey students. Find the total percentage of Bombay?
Ans:  6%
38. An equilateral triangle of sides 3 inch each is given. How many equilateral triangles of side 1 inch can be formed from it?
Ans: 9
39. If A/B = 3/5,then 15A = ?
Ans : 9B
40. Each side of a rectangle is increased by 100% .By what percentage does the area increase?
Ans : 300%
41. Perimeter of the back wheel = 9 feet, front wheel = 7 feet on a certain distance, the front wheel gets 10 revolutions more than the back wheel .What is the distance?
Ans : 315 feet.
42. Perimeter of front wheel =30, back wheel = 20. If front wheel revolves 240 times. How many revolutions will the back wheel take?
Ans: 360 times
43. 20% of a 6 litre solution and 60% of 4 litre solution are mixed. What percentage of the mixture of solution
Ans: 36%
44City A's population is 68000, decreasing at a rate of 80 people per year. City B having population 42000 is increasing at a rate of 120 people per year. In how many years both the cities will have same population?
Ans: 130 years
45Two cars are 15 kms apart. One is turning at a speed of 50kmph and the other at 40kmph . How much time will it take for the two cars to meet?
Ans: 3/2 hours
46A person wants to buy 3 paise and 5 paise stamps costing exactly one rupee. If he buys which of the following number of stamps he won't able to buy 3 paise stamps.
Ans: 9
47There are 12 boys and 15 girls, How many different dancing groups can be formed with 2 boys and 3 girls.
48Which of the following fractions is less than 1/3
(a) 22/62
(b) 15/46
(c) 2/3
(d) 1

Ans: (b)
49There are two circles, one circle is inscribed and another circle is circumscribed over a square. What is the ratio of area of inner to outer circle?
Ans: 1 : 2
50Three types of tea the a,b,c costs Rs. 95/kg,100/kg and70/kg respectively.
     How many kgs of each should be blended to produce 100 kg of mixture worth Rs.90/kg,
     given that the quntities of band c are equal

a)70,15,15
b)50,25,25
c)60,20,20
d)40,30,30

Ans. (b)
51. in a class, except 18 all are above 50 years.
    15 are below 50 years of age. How many people are there

(a) 30
(b) 33
(c) 36
(d) none of these.

Ans. (d)
52. If a boat is moving in upstream with velocity of 14 km/hr and goes downstream with a velocity of 40 km/hr, then what is the speed of the stream ?

(a) 13 km/hr
(b) 26 km/hr
(c) 34 km/hr
(d) none of these

Ans. A
53. Find the value of ( 0.75 * 0.75 * 0.75 - 0.001 ) / ( 0.75 * 0.75 - 0.075 + 0.01)

(a) 0.845
(b) 1.908
(c) 2.312
(d) 0.001

Ans. A
54. A can have a piece of work done in 8 days, B can work three times faster than the A, C can work five times faster than A. How many days will they take to do the work together ?

(a) 3 days
(b) 8/9 days
(c) 4 days
(d) can't say

Ans. B
55. A car travels a certain distance taking 7 hrs in forward journey, during the return journey increased speed 12km/hr takes the times 5 hrs.What is the distance travelled

(a) 210 kms
(b) 30 kms
(c) 20 kms
(c) none of these

Ans. B
56. Instead of multiplying a number by 7, the number is divided by 7. What is the percentage of error obtained ?
57.  Find (7x + 4y ) / (x-2y) if x/2y = 3/2 ?

(a) 6
(b) 8
(c) 7
(d) data insufficient

Ans. C
58. A man buys 12 lts of liquid which contains 20% of the liquid and the rest is water. He then mixes it with 10 lts of another mixture with 30% of liquid.What is the % of water in the new mixture?
59. If a man buys 1 lt of milk for Rs.12 and mixes it with 20% water and sells it for Rs.15, then what is the percentage of gain?
60. Pipe A can fill a tank in 30 mins and Pipe B can fill it in 28 mins.If 3/4th of the tank is filled by Pipe B alone and both are opened, how much time is required by both the pipes to fill the tank completely ?
61. If on an item a company gives 25% discount, they earn 25% profit. If they now give 10% discount then what is the profit percentage.
(a) 40%
(b) 55%
(c) 35%
(d) 30%

Ans. D
62. A certain number of men can finish a piece of work in 10 days. If however there were 10 men less it will take 10 days more for the work to be finished. How many men were there originally?

(a) 110 men
(b) 130 men
(c) 100 men
(d) none of these

Ans. A
63. In simple interest what sum amounts of Rs.1120/- in 4 years and Rs.1200/- in 5 years ?
(a) Rs. 500
(b) Rs. 600
(c) Rs. 800
(d) Rs. 900

Ans. C
64. If a sum of money compound annually amounts of thrice itself in 3 years. In how many years
will it become 9 times itself.

(a) 6
(b) 8
(c) 10
(d) 12

Ans A
65. Two trains move in the same direction at 50 kmph and 32 kmph respectively. A man in the slower train
observes the 15 seconds elapse before the faster train completely passes by him.
What is the length of faster train ?

(a) 100m
(b) 75m
(c) 120m
(d) 50m

Ans B
66. How many mashes are there in 1 squrare meter of wire gauge if each mesh
is 8mm long and 5mm wide ?

(a) 2500
(b) 25000
(c) 250
(d) 250000

Ans B
67. x% of y is y% of ?
(a) x/y
(b) 2y
(c) x
(d) can't be determined

Ans. C
68. The price of sugar increases by 20%, by what % should a housewife reduce the consumption of sugar so that expenditure on sugar can be same as before ?
(a) 15%
(b) 16.66%
(c) 12%
(d) 9%

Ans B
69. A man spends half of his salary on household expenses, 1/4th for rent, 1/5th for travel expenses, the man deposits the rest in a bank. If his monthly deposits in the bank amount 50, what is his monthly salary ?
(a) Rs.500
(b) Rs.1500
(c) Rs.1000
(d) Rs. 900

Ans C
70. The population of a city increases @ 4% p.a. There is an additional annual increase of 4% of the population due to the influx of job seekers, find the % increase in population after 2 years ?
71. The ratio of the number of boys and girls in a school is 3:2 Out of these 10% the boys and 25% of girls are scholarship holders. % of students who are not scholarship holders.?
72. 15 men take 21 days of 8 hrs. each to do a piece of work. How many days of 6 hrs. each would it take for 21 women if 3 women do as much work as 2 men?
(a) 30
(b) 20
(c) 19
(d) 29

Ans. A
73. A cylinder is 6 cms in diameter and 6 cms in height. If spheres of the same size are made from the material obtained, what is the diameter of each sphere?
(a) 5 cms
(b) 2 cms
(c) 3 cms
(d) 4 cms

Ans C
74. A rectangular plank (2)1/2 meters wide can be placed so that it is on either side of the diagonal of a square shown below.(Figure is not available)What is the area of the plank?
Ans :7*(2)1/2
75. The difference b/w the compound interest payble half yearly and the simple interest on a
certain sum lent out at 10% p.a for 1 year is Rs 25. What is the sum?
(a) Rs. 15000
(b) Rs. 12000
(c) Rs. 10000
(d) none of these

Ans C
76. What is the smallest number by which 2880 must be divided in order to make it into a
perfect square ?

(a) 3
(b) 4
(c) 5
(d) 6

Ans. C
77. A father is 30 years older than his son however he will be only thrice as old as the son after 5 years
what is father's present age ?

(a) 40 yrs
(b) 30 yrs
(c) 50 yrs
(d) none of these

Ans. A
78. An article sold at a profit of 20% if both the cost price and selling price would be Rs.20/- the profit would be 10% more. What is the cost price of that article?
29. If an item costs Rs.3 in '99 and Rs.203 in '00.What is the % increase in price?

(a) 200/3 %
(b) 200/6 %
(c) 100%
(d) none of these

Ans. A
80. 5 men or 8 women do equal amount of work in a day. a job requires 3 men and 5 women to finish the job in 10 days how many woman are required to finish the job in 14 days.

a) 10
b) 7
c) 6
d) 12

Ans 7
81. A simple interest amount of rs 5000 for six month is rs 200. what is the anual rate of interest?

a) 10%
b) 6%
c) 8%
d) 9%

Ans 8%
82. In objective test a correct ans score 4 marks and on a wrong ans 2 marks are ---. a student score 480 marks from       150 question. how many ans were correct?
a) 120
b) 130
c) 110
d) 150

Ans130.
83. An artical sold at amount of 50% the net sale price is rs 425 .what is the list price of the artical?

a) 500
b) 488
c) 480
d) 510

Ans 500
84. A man leaves office daily at 7pm  A driver with car comes from his home to pick him from office and bring back home 
     One day he gets free at 5:30 and instead of waiting for driver he starts walking towards home.
     In the way he meets the car and returns home on car  He reaches home 20 minutes earlier than usual.
     In how much time does the man reach home usually??

Ans. 1hr 20min
85. A works thrice as much as B. If A takes 60 days less than B to do a work then find the number of days it would take to       complete the work if both work together?
Ans. 22½days
86. How many 1's are there in the binary form of  8*1024 + 3*64 + 3
Ans. 4
87. In a digital circuit which was to implement (A B) + (A)XOR(B), the designer implements (A B) (A)XOR(B) 
    What is the probability of error in it ?

88. A boy has Rs 2. He wins or loses Re 1 at a time  If he wins he gets Re 1 and if he loses the game he loses Re 1.
     He can loose only 5 times. He is out of the game if he earns Rs 5.
     Find the number of ways in which this is possible?

Ans. 16
89. If there are 1024*1280 pixels on a screen and each pixel can have around 16 million colors
     Find the memory required for this?

Ans. 4MB
90. On a particular day A and B decide that they would either speak the truth or will lie.
     C asks A whether he is speaking truth or lying?
     He answers and B listens to what he said. C then asks B what A has said  B says "A says that he is a liar"
     What is B speaking ?

(a) Truth
(b) Lie
(c) Truth when A lies
(d) Cannot be determined

Ans. (b)
91. What is the angle between the two hands of a clock when time is 8:30
Ans. 75(approx)
92. A student is ranked 13th from right and 8th from left. How many students are there in totality ?
93. A man walks east and turns right and then from there to his left and then 45degrees to
  his right.In which direction did he go

Ans. North west

94. A student gets 70% in one subject, 80% in the other. To get an overall of 75% how much should get in third subject.
95. A man shows his friend a woman sitting in a park and says that she the daughter of my  grandmother's only son.
    What is the relation between the two

Ans. Daughter


96.  How many squares with sides 1/2 inch long are needed to cover a rectangle that is 4 ft long and 6 ft wide
(a) 24
(b) 96
(c) 3456
(d) 13824
(e) 14266

97. If a=2/3b , b=2/3c, and c=2/3d what part of d is b/
(a) 8/27
(b) 4/9
(c) 2/3
(d) 75%
(e) 4/3

Ans. (b)
2598Successive discounts of 20% and 15% are equal to a single discount of
(a) 30%
(b) 32%
(c) 34%
(d) 35%
(e) 36

Ans. (b)
99. The petrol tank of an automobile can hold g liters.If a liters was removed when the tank was full, what part of the full tank was removed?
(a)g-a
(b)g/a
(c) a/g
(d) (g-a)/a
(e) (g-a)/g

Ans. (c)
100. If x/y=4 and y is not '0' what % of x is 2x-y

(a)150%
(b)175%
(c)200%
(d)250%

Ans. (b)

math.h

 Mathematics is relatively straightforward library to use again. You must #include and must remember to link in the math library at compilation:
   cc mathprog.c -o mathprog -lm
A common source of error is in forgetting to include the file (and yes experienced programmers make this error also). Unfortunately the C compiler does not help much. Consider:

double x;
x = sqrt(63.9);
Having not seen the prototype for sqrt the compiler (by default) assumes that the function returns an int and converts the value to a double with meaningless results.

Math Functions

Below we list some common math functions. Apart from the note above they should be easy to use and we have already used some in previous examples. We give no further examples here:
double acos(double x) -- Compute arc cosine of x.
double asin(double x) -- Compute arc sine of x.
double atan(double x) -- Compute arc tangent of x.
double atan2(double y, double x) -- Compute arc tangent of y/x.
double ceil(double x) -- Get smallest integral value that exceeds x.
double cos(double x) -- Compute cosine of angle in radians.
double cosh(double x) -- Compute the hyperbolic cosine of x.
div_t div(int number, int denom) -- Divide one integer by another.
double exp(double x -- Compute exponential of x
double fabs (double x ) -- Compute absolute value of x.
double floor(double x) -- Get largest integral value less than x.
double fmod(double x, double y) -- Divide x by y with integral quotient and return remainder.
double frexp(double x, int *expptr) -- Breaks down x into mantissa and exponent of no.
labs(long n) -- Find absolute value of long integer n.
double ldexp(double x, int exp) -- Reconstructs x out of mantissa and exponent of two.
ldiv_t ldiv(long number, long denom) -- Divide one long integer by another.
double log(double x) -- Compute log(x).
double log10 (double x ) -- Compute log to the base 10 of x.
double modf(double x, double *intptr) -- Breaks x into fractional and integer parts.
double pow (double x, double y) -- Compute x raised to the power y.
double sin(double x) -- Compute sine of angle in radians.
double sinh(double x) - Compute the hyperbolic sine of x.
double sqrt(double x) -- Compute the square root of x.
void srand(unsigned seed) -- Set a new seed for the random number generator (rand).
double tan(double x) -- Compute tangent of angle in radians.
double tanh(double x) -- Compute the hyperbolic tangent of x.

Math Constants

The math.h library defines many (often neglected) constants. It is always advisable to use these definitions:

HUGE -- The maximum value of a single-precision floating-point number.
M_E -- The base of natural logarithms (e).
M_LOG2E -- The base-2 logarithm of e.
M_LOG10E - The base-10 logarithm of e.
M_LN2 -- The natural logarithm of 2.
M_LN10 -- The natural logarithm of 10.
M_PI -- $\pi$.
M_PI_2 -- $\pi$/2.
M_PI_4 -- $\pi$/4.
M_1_PI -- 1/$\pi$.
M_2_PI -- 2/$\pi$.
M_2_SQRTPI -- 2/$\sqrt{\pi}$.
M_SQRT2 -- The positive square root of 2.
M_SQRT1_2 -- The positive square root of 1/2.
MAXFLOAT -- The maximum value of a non-infinite single- precision floating point number.
HUGE_VAL -- positive infinity.
There are also a number a machine dependent values defined in #include -- see man value or list value.h for further details.

Monday, December 7, 2009

Chain Cut Problem

Problem:

What is the least number of links you can cut in a chain of 21 links to be able to give someone all possible number of links up to 21 

Solution:

Assume that a chain of length k for every 1<=k<=length(chain)
  must be doable with the open links. Then you can reach

  links  length    dissection

    0      1         1
    1      5         1-(1)-3
    2     13         1-(1)-3-(1)-7
    3     29         1-(1)-3-(1)-7-(1)-15
    4     61         1-(1)-3-(1)-7-(1)-15-(1)-31
    n   2^(n+2)-3

we have taken links as 2^k-1...and hence get such answer.

The question can be modified a bit...
You are having 31kg of rice. You are provided with a 1kg stone for weighing. In how many weights the 31kg of rice can be weighed.
Now we can't have empty selection...so for 
n we have 2^(n+1)-3...
so we have 2^(n+1)-3 = 31
n+1 = 6 (because 2^5 < 35 < 2^6 )
n=5

CTS Aptitude Question paper(Yellow)

Question 1:
If all the 6 are replaced by 9, then the algebraic sum of all the numbers from 1 to 100(both inclusive) varies by
Answer: 330

Question 2:
The total no. of numbers that are divisible by 2 or 3 between 100 and 200(both inclusive) are?
Answer: 67

Question 3:
From a pack of cards Jack, Queen, King & ace are removed. Then the algebraic sum of rest of the cards is?
Answer: 216

Question 4:
The average temperature of days from Monday to Wednesday is 37 degree Celsius and that of from Tuesday to Thursday is 34 degrees. The temperature of Thursday is 4/5th of Monday. Then the temperature of Thursday is
Answer: 36 degrees

Question 5:
Swetha, Tina, Uma and Vidya are playing a gambling. In this different people lose in different games-in the reverse alphabetical order. The rule is that if one loses she should double the amount of others. At the end of 4th game each of them have same amount of money (Rs.32).
5(a): Which one of them started with the least amount?
5(b): Which one of them started with the largest amount of money?
5(c): At the end of the 2nd game what is the amount of money with uma?
Answer:  5(a): Vidya,
                5(b): Swetha,
                5(c): Rs.8


Question 6:
A cube of 12 mm is painted on all its side. If it is made up of small cubes of size 3mm. If the big cube is splitted into those small cubes, the number of cubes that remain unpainted is?
Answer: 8

Question 7: 
B is 50% faster than A. If A starts at 9 A.M. and B starts at 10 A.M. A travels at a speed of 50 km/hr. If A and B are 300 kms apart, The time when they meet when they travel in opposite direction is?
Answer: 12 noon

Question 8:
A graph will be there. Inside the graph sheet there will be a Quadrilateral. We have to count the number of squares in the Quadrilateral.
Answer:

Question 9:
You are having 31kg of rice. You are provided with a 1kg stone for weighing. In how many weights the 31kg of rice can be weighed.
Answer: 5

Question 10:
A starts at 11:00AM and travels at a speed of 4km/hr. B starts at 1:00PM and travels at 1km/hr for the first 1hr and 2km/hr for the next hr and so on. At what time they will meet each other.
Answer:

Question 11:
There are 80 coins, among them one coin weighs less compared to other. You are given a physical balance to weigh. In how many wieghings the odd coin can be found.
Answer:

Question 12:
Dia of the circle 4cm. The shaded part is 1/3 of the square area. What is the side of the square?
Answer: root of 3pi

Question 13:
A,B,C, can do a work in 8,14,16 days respectively. A does the work for 2 days. B continues from it and finishes till 25% of the remaining work. C finishes the remaining work. How many days would have taken to complete the work?
Answer:

Question 14:
Raja went to a beauty contest .his wife was eager to know the result he told that the lady wear a yellow sari was winner. Miss. Andhra Pradesh Miss. Utter Pradesh, Miss. Maharashtra, Miss. West Bengal were the participants all the participants sat in a row. The conditions are:-
               (A) The woman wore yellow sari won the competition.
               (B) Miss. West Bengal was neither the runner-up or winner.
               (C) Miss. West Bengal was not at either ends.
               (D) Miss. Maharastra wore the white sari.
               (E) The women wore white sari and yellow sari sat at extreme ends.
               (F) The runner-up and winner did not sit together.
[This was the passage given and the questions were easy]
Answer:

Question 15:
The ratio of white balls and black balls is 1:2. If 9 gray balls is added it becomes 2:4:3. Then what is number of black balls?
Answer:12

Question 16:
There are 10 coins. 6 coins showing head. And 4 showing tail. Each coin was randomly flipped (not tossed) seven times successively.after flipping the coins are 5 heads 4 tails one is hided the hided coin will have what?
Answer:

Question 17:
Two cars are 500 cm apart. each is moving forward for 100 cm at a velocity of 50 cm/s and receding back for 50 cm at 25 cm/s at what time they will collide with each other.
Answer:

Question 18:
People near the sea shore are leading a healthy life as they eat fish.but people at other part of the city are also healthy. Inference.
Answer:

Question 19:
It is found from research that if u r a drunken then u have a less chance for chronic heart diseases. Inference.
Answer:

Question 20:
A-B+c>A+B-C
         i) B is +ve,
         ii) B is ?ve when it will hold true.
Answer:

Question 21:
i) C.P is Rs 120 and profit is 30%
ii) C.P is Rs 210 and profit is 20%
we can find the S.P by using
           i)only i
           ii)only ii
           iii)both i & ii
           iv)neither i & ii
Answer:

Question 22:
How will u find distance between Nagpur and Mumbai?
I took one hour more when I travel at 80 km/hr than at 90 km/hr.
Answer:

Question 23:
100 coins were collected by four persons each collected more than 10 each collected a different number each was an even number find what is the max possible no of coins? (Two more questions based on the same passage.)
Answer:

Question 24:
A car travels from B at a speed of 20 km/hr. The bus travel starts from A at a time of 6 A.M. There is a bus for every half an hour interval. The car starts at 12 noon. Each bus travels at a speed of 25 km/hr. Distance between A and B is 100 km. During its journey , The number of buses that the car encounter is:
Answer:

Question 25:
The ratio of the ages of the father and the son is 5:3, After 10 years it will be in the ratio 3:2. What will be their ages.
Answer:

Question 26: 
There was a Island. In that Island there was Rubys and Emeralds. Those were available in plenty. 0.3 kg of ruby is 4 lakhs and 0.4 kg of emeralds is 5 lakhs. Jayanth is buying 12 kg of Ruby and emerald. (Choices will be given.)
Jayanth has to carry both ruby and emerald to the maximum profit.
Answer:

Question 27:
Varun buys 8 books,10 pens and 2 pencils and Babu buys 6 books, 5pens and 5 pencils. Babu pays 50% more than Varun. What is the amount Varun spends in buying pencils.
Answer:

Question 28:
Prakash and Revathi rent a fancy shop. Prakash imposes the following restrictions on Revathi for buying clips,stickers and lip sticks. The number of clips is twice the no. of stickers. The no. of lipsticks should be more than the sum of clips and stickers. Cost of clip is 1 rupee. Cost of lipstick is twice the clips. Cost of 1 lipstick is the cost of four stickers. Then What is the amount that Prakash spents for Revathi. (Answer choices will be given.)
Answer: