Question

Thr ratio of boys to girls in a class is 4:5. If the number of boys is 20 then number of girls is?

Answer 1

Let x and y be the no. of boys and girls in the class.
Then,
x/y = 4/5
=> 20/y = 4/5 [Given that x = no. of boys = 20]
=> 4y = 20×5
=> 4y = 100
=> y = 100/4
=> y = 25
Therefore the no. of girls in the class is 25