You can
put this solution on YOUR website!Remember, if the diameter is 30, then the radius is 15
The volume of a cylinder can be found by the formula
Now plug in

and
V =
Edit: Now divide that result by 231 to convert from cubic inches to gallons to get

. So the tank can approximately hold 147 gallons (after rounding). Note: 1 gallon = 231 cubic inches.