Question

There are 10 boys and 20 girls in a class.

The class has a test.

The mean mark for all the class is 60.
The mean mark for the girls is 54.

Work out the mean mark for the boys.

Answer 1

There are 10 + 20 = 30 total students in the class.

Total marks for the class = 60 * 30 = 1800.

Total marks for the girls = 54 * 20 = 1080.

=> Total marks for the boys = 1800 - 1080 = 720.

Mean mark for the boys = 720 / 10 = 72.