The average weight of P and his four friends is 52.4 kg. If P is 3 kg lighter than the average weight of his four friends, find the weight of P (in kg).
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 50.
total weight of all 5 = 52.4 × 5 = 262 kg
Let the average weight of P's 4 friends be x kg
Then their total weight = 4x
P is 3 kg lighter than the average of the 4 friends ⇒ P = x − 3
P + 4 friends = (x − 3) + 4x = 5x − 3
⇒ 5x − 3 = 262 ⇒ 5x = 265 ⇒ x = 265/5 = 53
⇒ P = x − 3 = 53 − 3 = 50 kg