The average age of a class is 40 years. If 12 new students with an average age of 32 years join the class, the overall average decreases by 4 years. Find the original strength of the class.

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.