There are a total of 42 computers . Each computer runs one of three operating systems: OSX ,Windows ,Linux .The ratio of the computers running OSX ,Windows, Linux is 2:5:7. Find the number of computers that are running each of the operating systems.

Let's x is the ratio between them

Then,

2x+ 5 x + 7 x = 42

14 x = 42

x = 42 / 14

X = 3

2 x = 2 ( 3) = 6 OSX

5 x = 5 ( 3) = 15 Windows

7 x = 7 x(3) = 21 Linux

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All the six members of a family A. B. C. D. E and F are travelling together. B is the son of C but C is not the mother of B, A and C are married couple. E is the brother of C. D is the daughter of A.F is the brother of B. How many children does A have?

B is the son of C but C is not a mother of B means C is the father of B. A is the married to C means A is the mother of B. F is the brother of B means F is son of A and C. D is daughter of A means D is daughter A and C.A has son B,son F and daughter D i. e. ,three children..

K is the brother of N and X,Y is the mother of N and Z is the father of K. Which of the following statement is not definitely true.

K is the brother of N and X . so ,Y who is the mother of N and Z , who is the father of K ,will be mother and father of all three. however ,it is not mentioned whether N is male or female..

Bell and Stacy are two sisters. The sum of the ages of Stacy and Bell is 80. Before ten years from now, Bell age was twice as stacy's age. How old is Elder sister now?

1st Condition:

B+S=80.......(1)

2nd Condition:

2S-B=10...........(2)

By solving these equation:

B=50 and S=30

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___, IPC, LTY, PWT, UYN, AZG.

Find the missing?

The given series is a mixed series.

Pattern for the first letter:

G+1=I, I+2=L, L+3=P, P+4=U, U+5=A

Pattern with gaps for the second letter:

K+5=P, P+4=T, T+3=W, W+2=Y, Y+1=Z

Pattern for the third letter:

F-2=C, C-3=Y, Y-4=T, T-5=N, N-6=G,

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All the 6 members of a family A.B.C.D.E.and F are traveling together . B is the son or C but C is not the mother of B ,A and C are a married couple . E is the brother of C.D is the daughter of A.F is the brother of B.

How many male members are there in the family?

B is the son of C is not the mother of B means C is the father of B.A is married to C means A is the mother of B .F is brother 0f B means F is son of A and C.D is daughter of A means D is daughter A and C. A is the mother and hence female .B is the son and hence male. C is the husband and hence female. D is the daughter and hence female. E is the brother and hence male. F is the son and hence male. So, there are four males..

In following alphabet series , one term missing as shown by question mark . Choose missing term from options.

ejo, tyd, ins, xch, ?

There is a gap of four letters between the first and second, the second and third letters of each term, and also between the last letter of a term and the first letter of the next term.

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Atif is notified by a policeman from a distance of 200 m. The thief starts running and the police man chases him. The thief and the policeman run at the rate of 10 km and 11 km per hour respectively ,what is the distance between them after 6 minutes?

Relative speed of thief and policeman=(11-10)km/hr=1 km/hr.

Distance covered in 6 minutes=[(1/60)*6]km=(1/10)km=100m.

Distance between the thief and the policeman=(200-100)m=100m.

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In a 100m race a once with a speed of 1.66 metre per second. If a give a start of 4 minute to be and still beats him by 12 seconds. What is the speed of B?

Time taken by a to cover hundred metres =60 seconds

Since a gives a start of 4 minutes then time taken by b =72 seconds

B takes 72 second to cover 96 meters

speed of B =96 / 8

72 = 1.33 meter per second.

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