Question

The average weight of 45 students of a class is
42 kg. If nine students with an average weight of
42 kg leave the class and nine more students with
an average weight of 48 kg join the class, then what
would be the new average weight of the class?
(1) 41.4 kg
(2) 42 kg
(3) 42.6 kg
(4) 43.4 kg
(5) None of these​

Answer 1

Answer:

43.2

Step-by-step explanation:

45×42-42×9+48×9=1944

new average=1944/45=43.2