Question

The average weight of a family of 8 members is 56 kg. The grandfather and the grandmother came to visit the family. Now, the average weight of 10 members of the family is 64 kg. Find the average weight (in kg) of the grandparents.

• A. 92
• B. 94
• C. 96
• D. 90

Answer 1

Answer:

C. 96

Total weight of 8 members

$8 \times 56 = 448 \text{ kg}$
Total weight of 10 members

$10 \times 64 = 640 \text{ kg}$
Weight of grandparents

$640 - 448 = 192 \text{ kg}$
Average weight of grandparents

$\frac{192}{2} = 96 \text{ kg}$