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.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e 96.
Total weight of 8 members
Average = 56, so total = 56 × 8 = 448 kg
Total weight of 10 members
Average = 64, so total = 64 × 10 = 640 kg
Combined weight of grandparents = 640 − 448 = 192 kg
Average weight of grandparents = 192 ÷ 2 = 96 kg