A family consists of grandparents, parents and three grandchildren. The average age of the grandparents is 67… · ABC26GN1570
Subject: General Aptitude · Chapter: Average
A family consists of grandparents, parents and three grandchildren. The average age of the grandparents is 67 years, that of the parents is 35 years and that of the grandchildren is 6 years. What is the average age of the family?
(a)$28 \frac{4}{7}$ years
(b)$31 \frac{5}{7}$ years
(c)$32 \frac{1}{7}$ years
(d)None of these
Answer
Answer (as printed): B
Explanation
Required average $=\left(\frac{67 \times 2+35 \times 2+6 \times 3}{2+2+3}\right)$ $$=\left(\frac{134+70+18}{7}\right)=\frac{222}{7}=31 \frac{5}{7} \text { years. }$$
Explanation as extracted from the printed page; notation may be imperfect.