In a class of 60, where girls are twice that of boys, Kamal ranked seventeenth from the top. If there are 9 girls ahead of Kamal, how many boys are after him in rank?

12

According to the question:

Number of girls = Twice of boys (Girls = 40 and Boys = 20)

If Kamal ranks 17th from top that means, there are 16 students Infront of him out of which 9 are girls and 7 are boys, which indicates there are total 8 boys till 17th position. That means, after him there are 12 boys (20 - 8).