2021 · Q56
The average age of a husband and his wife was 23 years when they were married 5 years ago. The average age of the husband, the wife and their child is 20 years now. How old is the child now?
General Mental Ability, Quantitative Aptitude and StatisticsNumber system and arithmetic
- A9 months
- B1 year
- C3 years
- D4 years
Explanation
Let present ages of husband, wife and child be x, y and z years respectively. Given, ⇒ [(x – 5) + (y – 5)]/ 2 = 23 ⇒ x + y = 46 + 10 = 56 Given, ⇒ (x + y + z)/3 = 20 ⇒ x + y + z = 60 ⇒ 56 + z = 60 ⇒z=4 ∴ Child is 4 years old now.