The present average age of four members of a family is 27 years and the average increases by 3 years when one of their relatives joins them. The age of the relative is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 42 years.
Let the age of the relative be 'x'
We know that,
Average = Sum of observations/Number of observations
According to the question,
Average age = [(4 × 27) + x]/5
⇒ 30 = (108 + x)/5
⇒ 108 + x = 150
⇒ x = 150 - 108 = 42 years