Answer :
1 1/3 - 3/4 = 4/3 - 3/4 = 16/12 - 9/12 = 7/12 gallons of yellow paint left;
1 1/4 - 3/4 = 5/4 - 3/4 = 2/4 = 1/2 gallons of green paint left;
7/8 - 3/4 = 7/8 - 6/8 = 1/8 gallons of blue paint left;
1 1/4 - 3/4 = 5/4 - 3/4 = 2/4 = 1/2 gallons of green paint left;
7/8 - 3/4 = 7/8 - 6/8 = 1/8 gallons of blue paint left;