Don L. answered • 11/14/18

Fifteen years teaching and tutoring basic math skills and algebra

Hi Brianna, the ratio 5 to 3 tells us for every 8 people, 5 will be adults and 3 will be children. Let x represent the number of children at the concert. Set up a proportion representing the given information:

3 / 8 = x / 120

Cross multiply:

8x = 3 * 120, or 360

Divide by 8

x = 45

There were 45 children at the concert.

The number of adults at the concert is 120 - 45, or 75.

The ratio of adults to children, 75 / 45. Dividing both the numerator and denominator by 15 gives: 5 / 3.

Questions?