5 years ago, the average age of a family of 4 was 21 years. A baby having been born, the average age of the family is same today. The present age of the baby is?
Explanation:
Total age of family of 4, 5 years ago = 4 × 21 = 84 Age of each member increases by 5 years, hence total increase should be 4 × 5 = 20 years. ∴ Total age of these 4 members of the family, at present = 84 + 20 = 104 years.
Total age of family of 5 (including the baby), today = 5 × 21 = 105
∴ Age of baby = Total age of 5 members - Total age of 4 original members. = 105 - 104 = 1 year.
Hence, option (a).
» Your doubt will be displayed only after approval.
Help us build a Free and Comprehensive Preparation portal for various competitive exams by providing us your valuable feedback about Apti4All and how it can be improved.