Question

The ages of A and B are in the ratio 7:2 . Five years hence their ages will be in the ratio 8:3 Find the present age of B is​

Answer 1

Answer:

ok so it is very common that when ratio is given the first step is to take that age as x

so let age of A - 7x and age of B - 2x

After 5 years the age will become,

7x + 5 of A and 2x + 5 of B

and in question it is given as 7x +5/ 2x+5 = 8/3

after cross multiplication you get,

21x + 15 = 16x + 40

5x = 25

so x = 5 so age of B = 2× 5 = 10 years

Step-by-step explanation:

hope it helps....

Answer 2

Answer:

Let the age of A and B = 7x and 2x

After 5 years

Age of A = 7x+5

Age of B = 2x+5

7x+5 ÷ 2x+5 = 8÷3

3(7x+5) = 8(2x+5)

21x+15 = 16x + 40

21x- 16x = 40-15

5x= 25

x = 5

Present age of A = 7x= 7×5 = 35 years

Present age of B = 2x = 2×5 = 10 years