the average weight of 8 person ' s increases by 1.5 kg when a new person comes in place of one of them weighing 75 kg . what might be the weight of the new person ?
"total weight increased = ( 8 x 1.5 ) kg = 6 kg . weight of new person = ( 75 + 6 ) kg = 81 kg . answer : a"
add(multiply(8, 1.5), 75)