The average weight of A, B, C and D is 33 kg. C is 12 kg lighter than A, while B is 6 kg heavier than C. D's weight is 10 kg less than that of C. What is the average weight of A and D?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. 32 kg.
According to the question -
⇒ A = C + 12
⇒ B = C + 6
⇒ D = C - 10
Average weight of A, B, C and D = (A + B + C + D)/4
⇒ 33 = (A + B + C + D)/4
⇒ 33 × 4 = A + B + C + D
⇒ 132 = C + 12 + C + 6 + C + C - 10
⇒ 132 = 4C + 8
⇒ 132 - 8 = 4C
⇒ 124 = 4C
⇒ C = 31 kg
⇒ A = 31 + 12 = 43 kg
⇒ B = 31 + 6 = 37 kg
⇒ D = 31 - 10 = 21 kg
Thus,
Average weight of A and D = (A + D)/2
⇒ (43 + 21)/2
⇒ 64/2 = 32 kg