The average age of a family of 6 members is 25 years with the youngest member being 8 years old. What was the average age (in years) of the family just before the birth of the youngest member?

Question

Question

This question was previously asked in

RRB ALP Electrician 22 Jan 2019 Official Paper (Shift 3)

Answer 1

Given:

The average of 6 family members is 25 years old.

The age of the youngest member of the family is 8 years.

Formula used:

Average = (Sum of total observations)/(Total number of observation)

Calculation:

Average = (Sum of total observations)/(Total number of observation)

⇒ (Sum of total observations) = Average × (Total number of observation)

Total sum of family = 6 × 25 = 150 years

Age of child is 8 years old, before his birth all 5 member of family are 8 years less than present age

So, New sum of age of family = 150 – 8 × 6 = 102 years

The required average = 102/5 = 20.4 years

∴ The required average is 20.4 years.