21 cups is 1.3 (1.3125) gallons (US).
1.31 gal 1 gallon = 16 cups 1 cup = 0.06 gallon
21 gal 1 gallon = 16 cups 1 cup = 0.06 gallon
2 gal
1.31 gal 1 gallon = 16 cups 1 cup = 0.06 Gallon
2 cups
4 gal 1 gallon = 16 cups 1 cup = 0.06 Gallon
0.93 gal 1 gallon = 16 cups 1 cup = 0.06 Gallon
6.25 gal
17272144 cups
6 gal
There are 32 cups in 4 gallons.
5 gal 1 gallon = 16 cups 1 cup = 0.06 Gallon