Question

A 20-gallon container is filled halfway with a mixture that is $90\%$ vinegar and $10\%$ water. How many gallons of water must be added for the mixture to become $60\%$ vinegar and $40\%$ water

Answer 1

5 gallons of water must be added.

10 gallons to start with

adding 'x' gallons of water final volume = 10 + x

.9 (10) = amount of vinegar

.1(10) = amount of water

amount of vinegar before and after water addition is constant

.9(10) = .6(10+x)

9 = 6 + .6x

3 = .6x

x = 5 gallons of water to be added

(i truly hope i helped you