In this task, you need to provide the correct option for a given problem from the provided options.

Problem: a dog takes 4 leaps for every 5 leaps of a hare . if one leap of the dog is equal to 3 leaps of the hare , the ratio of the speed of the dog to that of the hare is : 
Options: a ) 12 : 5 , b ) 4 : 3 , c ) 9 : 5 , d ) 9 : 1 , e ) 9 : 2
a

Problem: the ratio of spinsters to cats is 2 to 7 . if there are 55 more cats than spinsters , how many spinsters are there ? 
Options: a ) 20 , b ) 21 , c ) 22 , d ) 23 , e ) 24
c

Problem: the ratio of number of boys and girls in a school is 3 : 2 . if there are 100 students in the school , find the number of girls in the school ? 
Options: a ) 25 , b ) 30 , c ) 35 , d ) 40 , e ) 50

d