Question

1 part cleaner to 3 part water. How much cleaning solution do I use?

Answer 1

A gallon is 4 quarts. 1 qt or cleaning solution to 3 qts of water.

1/4 of a gallon is cleaning solution (1 qt).
3/4 of a gallon is water (3 qts).

Answer 2

That depends on how much water you use, for instance 3 cups of water to 1 cup of cleaner.