Question

B's present age is 25% more than A's present age. If five years from now, the ratio of their ages i.e. A to B will be 5 : 6, then the present age of B is

Answer 1

Let  A's age be a

So B's age is a+a/4 = 5a/4

After five years their ages are a+5 and 5a/4 + 5

According to problem, (a+5)/(5a/4 + 5) = 5/6

⇒ (a+5)*4/(5a + 20) = 5/6

⇒ (4a+20)/(5a+20)=5/6

⇒(4a+20)*6 = (5a+20)*5

⇒24a + 120 = 25a + 100

⇒a = 20 years (A's age)

⇒5a/4 = 5*20/4 = 25 years (B's age)