The average weight of A, B and C is 65 kg. If the average weight of C and B is 61.5 kg, and the average weight of A and C is 68.5 kg, then the weight of C (in kg) is:

65 60 68 67

65

Sum of weights of A, B and C = 65 x 3 = 195 ....(1) Sum of weights of B and C = 61.5 x 2 = 123 .....(2) Sum of weights of A and C = 68.5 x 2 = 137 .....(3) Solving (1), (2) and (3) Weight of A ⇒ 195 - 123 = 72 Weight of C A + C = 137 ⇒ C = 137 - 72 = 65 kg ∴ Weight of C is 65 kg