Correct Answer - Option 3 : 12
In a class of 60, where girls are twice that of boys.
Let the number of boys be 'a'.
So, number of girls is '2a'.
According to question:
a + 2a = 60
⇒ 3a = 60
⇒ a = 60 ÷ 3
⇒ a = 20
So, there are 20 boys and 40 girls in the class.
Kamal ranked seventeenth from the top.
If there are 9 girls ahead of Kamal.
So, number of boys ahead of Kamal = (17 - 9) - 1
= 7
Therefore, number of boys behind of Kamal = 20 - 8
= 12
Hence, '12' is the correct answer.