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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There are 6 persons A B C D E and F. C is the sister of F.B is the brother of E' husband. D is the father of A and grandfather of F . There are two fathers three brothers and a mother in the group. Who is E' husband?

D is father of A and grandfather of F. So, A is father of F. Thus, D andbA 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. Clearly, A is E's husband..

Bicycle travel first How distance between two place with the speed of 5 kilometre per hour and rest of her sister is the speed of 20 km per hour. The average speed of bicycle is:

Let the total distance covered be" s "km

Total time taken,

=(s/2)/5+(s/2)/20

=5s/40

Average speed,

=s/(5s/40)

=s*(40/5s)

=8 km/hr

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A man and his wife have three sons, and every
of the sons have a sister. How many are there in the family?

Option (C)

There is only 1 girl since it says that every sons has 'a' sister, if there's only 1 girl. She will be a sister to all the three sons.

So 3 sons + 1 sister + both the parents = 6 members in the family.

.In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative.

ab _ bcbca _ _ c _ bab

The series is abcbc / bcaca / cabab. Thus, the series consists of three sequences. The first sequence begins with a, the second with b and the third with c. Each sequence consists of a letter followed by other two letters repeated twice.

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Excluding stoppages, the speed of train is 50 km per hour and including stoppages it is 40 km per hour. For how many minutes does the train stop per hour?

Due to stopages it is it covers 10 km less.

Time taken to cover 10 km= (10/50)*60 min = 12 min

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Miley have 24 pastries in box of strawberry ,chocolate and lemon with ratio of 2:3:1 find number of pastries with flavours in the box?

Let's ratio between them is x then,

2x +3x +1x=24

6x =24

X=24/6

X=4

2x=2(4)=8 strawberry

3x=3(4)= 12 chocolate

1 X = 1(4)= 4 lemon

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