The average weight of A, B and C is 60 kg. If the average weight of B and C is 50 kg and that of A and B is 52 kg, then what is the weight of B?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 24 kg
An average times the number of people gives their total weight, so each average is turned into a total first.
A + B + C \(=3\times60=180\) kg
B + C \(=2\times50=100\) kg, so A \(=180-100=80\) kg
A + B \(=2\times52=104\) kg, so B \(=104-80=24\) kg