There are 1650 students in a college. The difference between the number of boys and girls in the college is 400. What is the percentage of girls in the college ?

Let no. of boys be 'B' and no. of girls be 'G'

Here from given data,

B + G = 1650 .....(1)

B - G = 400 .....(2)

From (1) & (2), we get

2B = 2050

=> B = 1025

=> G = 1650 - 1025 = 625

Hence, the % of girls = 625 x 100/1650

=> 38% (approx).