Question

In a class of 60, girls are twice that of boys. arun is 17th from the top. if there are 9 girls ahead of arun then how many boys are after him?

Answer 1

number is different process is same

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 ?

Option: A. 3 B. 7 C. 12 D. 23 E. 32 Answer: C . 12

Justification:

Let the number of boys be x.  Then, numbers of girls = 2x.
.'. x + 2x = 60  or  3x = 60  or  x = 20.
So, number of boys = 20 and numbers of girls = 40.
Number of students behind Kamal in rank = (60 - 17) = 43.
Number of girls ahead of Kamal in rank = 9.
Number of girls behind Kamal in rank = 40 - 9 = 31.
.'. Number of boys behind Kamal in rank = 43 - 31 = 12.