In a class of 40 students, ratio of boys and girls is 3 : 2 and the average marks scored by boys is 42 and that by girls is 46. Then the average marks scored by the whole class is:

43.6

The correct answer is Option (2) → 43.6

We have,

Total number of students = 40

Ratio of boys and girls is 3 : 2

Now according to the question,

3x + 2x = 40

x = 8

3x = 24

and 2x = 16

The average marks scored by boys is 42 and that by girls is 46

Total marks of boys = 42 × 24 = 1008 , Total marks of girls = 46 × 16 = 736

Average =  \(\frac{sum \;  of \;observation}{number\;of \;observation}\)

= \(\frac{1008 + 736}{40}\) = 43.6