The average weight of some children in a group is 43 kg. If 4 children, whose weights are 49.2 kg, 48.8 kg, 51.4 kg, and 50.6 kg, join the group, the average weight of all the children now increases by 0.5 kg. The number of children initially in the group is:

What is the average number of students in B.Tech (220), M.Tech (140), and B.A (4344) courses together?

A class has two sections A and B, which have 36 and 44 students respectively. If the average weight of section A is 40 kg and that of section B is 35 kg, find the average weight of the whole class.