Question

Anyone willing to help me?

Answer 1

1/2

Explanation:

Probably of selecting a boy:

20/30 = 2/3

and brought 10 up to 20:

45/60 = 3/4

so Probably of selecting a boy and brought 10 up to 20:

2/3 x 3/4 = 2/4 = 1/2