The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively, what will be the new ratio? Pick:
A) 5:7
B) 3:9
C) 21:22
D) 1:2
E) 11:13
Explanation:   Originally, let the number of boys and girls in the college be 7x and 8x respectively.   Their increased number is (120% of 7x) and (110% of 8x).   (120/100*7x) and(110/100*8x)   42x/5 and 44x/5   The required ratio =(42x/5:44x/5)=21:22   Answer:21:22
<result>C</result>
The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively, what will be the new ratio?