Use the following formula:
3. Circular area with a conical profile
1.047 x surface radius squared x 1 (Radius is half the surface diameter of the area)
Convert Gallons to Litres
Convert Litres to Gallons
Imperial Gallons: multiply total gallons by 4.546.
Imperial: divide number of gallons by 0.22 e.g. 100 imperial gallons = 100/0.22 = 454.6 Litres.
US Gallons: multiply total gallons by 3.785.
U.S: divide no. of US gallons by 0.264 e.g. 100 US gallons = 100/0.264 = 378.8 Litres.
Radius is half the surface diameter of the area.
Squaring means multiplying the figure by itself.
A cubic metre contains 1000 litres of water.
To convert Cubic feet to cubic metres multiply by .0283.
To convert cubic yards to cubic metres multiply by 0.765.