Answer: 8.75 gallons
Explanation:
Let the quarts of paints used for the inside be represented by x.
Since Jack uses 19 more quarts of paint for the outside of a shed than for the inside, the outside will be: x + 19.
Then, the equation to solve the question will be:
x + (x + 19) = 89
2x + 19 = 89
2x = 89 - 19
2x = 70
x = 70/2
x = 35
He used 35quarts of paint for the inside.
Since 4 quarts = 1 gallon
35 quarts = 35/4gallon = 8.75gallons