Mohammed is 8 years older than Joy now. In five years’ time he will be twice as old as Joy. How old is Joy now?

Analyze the question: We're given the age gap between Mohammed and Joy now, and a relationship between their ages in 5 years. We need Joy's present age.

Concept: Let a variable stand for Joy's age now, write Mohammed's age in terms of it, then form an equation from the "in five years" condition.

Solution:

Let Joy's age now = x. Mohammed's age now = x + 8.

In 5 years:

• Joy = x + 5
• Mohammed = x + 8 + 5 = x + 13

Mohammed will be twice as old as Joy:

x + 13 = 2(x + 5) x + 13 = 2x + 10 13 − 10 = 2x − x x = 3

Check: Joy is 3, Mohammed is 11. In 5 years: Joy is 8, Mohammed is 16, and 16 = 2 × 8 ✓.

Answer: Joy is 3 years old now, which is option B.

Tip: For age problems, always add the same number of years to both people. The age difference never changes (here it stays 8). In 5 years, Mohammed is twice Joy's age, so the difference equals Joy's age then: 8 = x + 5, so x = 3. This is a quick shortcut.