## Father And Child

#### Problem

When I was 14 years old my father was 42 years old, which was three times my age. Now he is twice my age, how old am I?

#### Solution

Let `f` be the father's age and his child's age be `c`.

As the father is 42 14 = 28 years older than the child, `f` = `c` + 28.

At the moment `f` = 2`c`, hence 2`c` = `c` + 28, and so `c` = 28. That is, the father's child is now 28 years old.

Problem ID: 77 (May 2002) Difficulty: 1 Star