Question

The scale factor of two similar swimming pools is 4:7. The amount of a chlorine mixture to be added is proportional to the volume of water in the pool. If 3 cups of the chlorine mixture are needed for the smaller pool, how much of the chlorine mixture is needed for the larger pool?

Answer 1

It would require 5.25 cups.

Since the amount of chlorine mixture necessary is proportional to the volume of water in the pool, we will use the scale factor of the volume of the two pools, 4/7, to set up a proportion.

4/7 = 3/x

Cross multiply:
4*x = 3*7
4x = 21

Divide both sides by 4:
4x/4 = 21/4
x = 5.25