Question

The average mark of 100 students is 33 out of 50. They are divided into three divisions A, B and C with strengths 50,30 and 20 respectively. If the average marks of both A and B is 36 and that of both B and C is 30 then the average marks of class B is

Answer 1

Answer:

I am sure every one of you will be able to answer this in the following way

Step-by-step explanation:

Average of 70 students = 80.

Hence total marks of all the 70 students = 70x80 = 5600

Out of these 70, average of 40 students = 75

Hence total marks of these 40 students = 40x75 = 3000.

So the total marks of the remaining 30 students = 5600-3000 = 2600

Hence the average of the remaining 30 students = 2600/30 = 86.66