Question

In a joint family, the average age of grandparents is 67 years, the average age of parents is 35 years and that of three grand children is 6 years. What is the average age of the family ?

• A. 28$\frac{4}{7}$ years
• B. 31$\frac{5}{7}$ years
• C. 31$\frac{1}{2}$ years
• D. 29$\frac{4}{7}$ years

Answer 1

Answer: (B)

31$\frac{5}{7}$ years

Total age of grandparents = $2\times 67$ years = 134 years
Total age of parents = $2\times 35$ years = 70 years
Total age of three grand chindren = $3\times 6=18years$
Total age of family = 134 + 70 + 18 = 222 years
Number of member in the family = 7
Therefore Required average = $\frac{222}{7}years=31\frac{5}{7}years.$