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

CE, GI, KM, OQ, ?

The letters of each term are alternate and also the last letter of each term and the first letter of the next term are alternate.

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

Z, L, X, J, V, H, T, F, ?, ?

The given sequence consists of two series -- Z, X, V, T, ? and L, J, H, F, ?, both consisting of alternate letters in a reverse order.

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A and B are married couple. X and Y are brothers. X is the brother of A.

How is Y related to B?

Option (A)

A and B are husband and wife. Since X and Y are brothers, and X is the brother of A, Y is also the brother of A.

Thus, Y is the brother-in-law of B.

Hence, the answer is (a).

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P is the brother of Q and R. S is R's
mother. T is P's father. Which of the following statements cannot be definitely
true ?

Option (D)

P, Q, R are children of same parents. So, S who is R's mother and T, who is P's father will be mother and father of all three. However, it is not mentioned whether Q is male or female. So, (d) cannot be definitely true.

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In following questions, one term in number series is incorrect.

Find out the incorrect number 5, 27, 61, 122, 213, 340, 509

Find out the incorrect number 5, 27, 61, 122, 213, 340, 509

The correct sequence is 2

So, 27 is wrong and should be replaced by 3

There are 6 persons A, B, C ,D E and F. C is the sister of F. B is the brother of E,s husband. D is the father of A and grand father of F. There are two fathers three brothers and a mother in the group. How many male members are there in the group?

D is father of A and grandfather of F. So, A is father of F. Thus D and A are the two fathers. C is the sister of F. So, C is the daughter of A . Since there is only one mother it is evident that E is the wife of A and hence the mother of C and C and F. so B is brother of A. There are three brothers. So F is the brother of C. A, the father is male. B, the brother, is male. C, the sister is female. D, the grandfather, is male. E, the mother, is female. F, the brother, is male. So, there are 4 male..

Look at this series: 2, 4, 6, 8, 10, . . .

What number should come next?

What number should come next?

This is a simple addition series.

Each number increases by 2.

Like -

First number is 2

Second number = 2 + 2 =4

Third number = 4 + 2 = 6

Fourth number = 6 + 2 = 8

Fifth number = 8 + 2 = 10 and

Sixth number = 10 + 2 = 12

Hence, The answer is (b) 12..

There are two trains move towards Each Other 50 km per hour and 60 km per hour respectively. When they meet it is noted that faster train cover 50 km more than the other. Find the total distance travelled by them?

First train cover 10 kilometre more in every hour so for 50 km it has to run in 5 hour.

D=(50+60)*5=550km

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In a class of 60 students, the number of boys and girls participating in the annual sports is in the ratio 3 : 2 respectively. The number of girls not participating in the sports is 5 more than the number of boys not participating in the sports. If the number of boys participating in the sports is 15, then how many girls are there in the class ?

Let the number of boys and girls participating in sports be 3x and 2x respectively.

Then, 3x = 15 or x = 5.

So, number of girls participating in sports = 2x = 10.

Number of students not participating in sports = 60 - (15 + 10) = 35.

Let number of boys not participating in sports be y.

Then, number of girls not participating in sports = (35 -y).

Therefore (35 - y) = y + 5 , 2y , 30 , y = 15.

So, number of girls not participating in sports = (35 - 15) = 20.

Hence, total number of girls in the class = (10 + 20) = 30.

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