the average weight of 9 persons increases by 1.5 kg . if a person weighing 65 kg is replaced by a new person , what could be the weight of the new person ?
"total weight increases = 9 × 1.5 = 13.5 kg so the weight of new person = 65 + 13.5 = 78.5 kg answer c"
add(65, multiply(9, 1.5))