The average age of a husband and his wife was 23 years at the beginning of their marriage. After five years they have a one-year old child. The average age of the family of three, when the child was born, was

Explanation

Sum of ages of husband and wife at the time of their marriage = 23 × 2 = 46 years Child was 1 year old after 5 years, => child was born 4 years after the marriage. Sum of the husband and wife after 4 years = 4 years of husband + 4 years of wife => Total age = 46 + 8 = 54 years 54 (25) 54 => Required average = 3 = 18 years [Child's age was 0, when he was born] => Ans - (C)