The average weight of 8 person's increases by 2.5 kg when a new person comes in place of one of them weighing 66 kg. What might be the weight of the new person?  Select the correct option: A) 56 kg B) 90 kg C) 86 kg D) data inadequate E) none of these

Rationale: "c 86 kg total weight increased = ( 8 x 2.5 ) kg = 20 kg . weight of new person = ( 66 + 20 ) kg = 86 kg ."
Answer: C