The ages of two persons differ by 15 years. If 5 years ago, the age of the older person was twice that of the younger one, then their present ages (in years) are :

Correct option is D

Given:

Age difference = 15 years

5 years ago, older person’s age = 2 × younger person’s age at that time

Solution:

Let present age of younger person = x
Then, older person’s age = x + 15
Five years ago:

Younger = x - 5

Older = x + 15 - 5 = x + 10

From the condition;

x + 10 = 2(x - 5)

x + 10 = 2x − 10

10 + 10 = 2x − x

x = 20

So, present ages:

Younger = 20 years

Older = 20 + 15 = 35 years