Question

Five years ago, John was twice as old as his brother Jim. Three years from now, the sum of their ages will be 31. How old is Jim now?

Answer 1

Let the present age of Jim = x years

and present age of John = y years

According to the given condition

(y – 5) = 2 (x – 5)

⇒ y – 5 = 2x – 10

⇒ y = 2x – 5 ...... (1)

Again, according to the given condition

(y + 3) + (x + 3) = 31

⇒ x + y = 25

⇒ x + 2x – 5 = 25 [ Using (1) ]

⇒ 3x = 30

⇒ x = 10

Hence, the present age of Jim is 10 years