Question

The average weight of 25 students of group A of a class is 51 kg. Whereas average weight of 35 students of group B is 54 kg. Find the average weight of 60 students of this class

Answer 1

Average weight of 25 students of group A = 51 kg
Thus, total of weight of 25 students
$W_1=51\times 25=1275kg$
Average weight of 35 students of group B = 54 kg
Thus, sum of weight of 35 students,$W_2=54\times 35=1890kg$
$\therefore$ Average weight of 60 students of class
$\frac{W_1+W_2}{60}$
$\frac{1275+1890}{60}=\frac{3165}{60}=52.75kg$