The present age of three brothers are in proportion 3:4:5. After five years , the sum of their ages 75. Find their ages after 5 years (in years).

Let the present ages be 3x,4x and 5x years respectively.

Then, (3x+5)+(4x+5)+(5x+5)=75

12x=60

x=5

So, after five years their ages 20 years,25 years, 30 years respectively.

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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..

In the class of 10 boys and 5 girls boys have 4 balls each and girls have 1 ball each what will be the average number of balls in class?

={( number of boys X number of balls)+( number of girls X number of balls)}/ total students

={(10Ã—4)+(5Ã—1)}/10+5

=(40+5)/15

= 3 is the average number of balls in class.

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