MATHS
posted by LARA on .
The ratio of the number of males to the females at a performance is 5 : 7.
1/4 of the males and 3/4 of the females are children. What is the ratio of the number of adults to children?
Express your answer in simplest form.

Let's say there are 5x males and 7x females. Now, to divide things up into quarters, let's call that 20y males and 28y females.
That means there are 5y+21y=26y children
So, 26y of the 48y people are children, leaving 22y as adults.
Thus, the adult:children ratio
22:26 = 11:13