The present average age of a family of five members is 26 years. If the present age of the youngest member in the family is ten years, then what was the average age of the family at the time of the birth of the youngest member ? (Assume no death occurred in the family since the birth of the youngest)

A 19 years

B  16 years

C 18 years

D 20 years

Solution

Correct Answer: Option D

Present total age of the members = 26(5) = 130 years.

 

Present age of the youngest member = 10 years

 

Present total age of the remaining four members = 130 -10 = 120 years

 

Their average age at the time of the birth of the youngest member = \(\frac{\left[120-\left(4\times10\right)\right]}4\) = 30 - 10 = 20 years.

Practice More Questions on Our App!

Download our app for free and access thousands of MCQ questions with detailed solutions