Question

IB exams

The average weight of 16 boys in a class is 50.25 kg and that of the remaining 8 boys is 45.15 kg. Find the average weights of all the boys in the class.

Answer 1

average weight of 16 boys = 50.25 kg
therefore , total weight of 16 boys = (50.25 * 16)kg
                                                 = 804 kg
average weight of 8 boys = 45.15 kg
therefore , total weight of 8 boys = (45.15 * 8) kg
                                               = 361.2 kg.
total number of boys = 16 + 8
                              = 24
total weight of 24 boys = 804 + 361.2
                                 = 1165.2 kg
therefore , average weight of 24 boys = (1165.2 / 24) kg
                                                      = 48.55 kg.