Question

The number of boys in a class is 30 and the number of girls is x. The mean of the number of boys and girls is 35.
If the number of girls is increased by 10 , what will be the new mean?

Answer 1

The number of girls are given as x.

$\frac{x+30}{2}$ = 35

$\Rightarrow$ x + 30 = 70

$\Rightarrow$ x = 40

If the number of girls is increased by 10 , their numbers become 40 + 10 = 50

New mean = $\frac{30+50}{2}$ = $\frac{80}{2}$ = 40