when a student joe , weighing 44 kg , joins a group of students whose average weight is 30 kg , the average weight goes up by 1 kg . subsequently , if two students , excluding joe , leave the group the average weight comes back to 30 kg . what is the difference between the average weight of the two students who left and the weight of joe ?
"after two persons leave the group the average remains the same . that means the weight of the two persons = 44 + 30 = 74 so , the average the two persons = 37 that gives the answer 44 - 37 = 7 answer e"
subtract(44, divide(subtract(add(multiply(30, subtract(44, add(30, 1))), 44), multiply(subtract(subtract(44, add(30, 1)), 1), 30)), const_2))