The average weight of P, Q, and R is 45 kg. If the average weight of P and Q is 40 kg, and that of Q and R is 43 kg, what is the weight of R?
Show answer & explanation
Correct answer: B
Explanation
Given:
Average of P, Q, and R = 45 kg
Average of P and Q = 40 kg
Average of Q and R = 43 kg
According to the formula:
Average = Sum of values / Number of values
P + Q + R = 45 × 3 = 135
P + Q = 40 × 2 = 80
Q + R = 43 × 2 = 86
R = (P + Q + R) − (P + Q)
= 135 − 80
= 55 kg