The average weight of a group of 8 people is 70 kg. After a new person joins the group, the average weight becomes 72 kg. What is the weight (in kg) of the new person?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 88.
Total weight of 8 people = 8 × 70 = 560 kg
New average = 72 kg for 9 people → Total weight = 9 × 72 = 648 kg
Weight of new person = 648 - 560 = 88 kg