The average weight of 10 persons increases by 7.9 kg when a new person replaces one of them weighing 20 kg. What is the weight of the new person?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 99 kg.
Let's assume the average weight of the 10 people = x kg and, the weight of the new person = W
Now, according to the question,
⇒ (10x - 20 + W)/10 = x + 7.9
⇒ 10x - 20 + W = 10x + 79
⇒ W = 99 kg