I have a tank that is 10 feet in diameter that I want to put floating degreaser in.The rate for the degreaser is 1/2 gallon per square foot of surface water.How do I figure out how many gallons I need?

Charlie,

The area of a circle is π r^{2} where r is the radius and π is approximately 3.14159. Thus for your circular surface the area is

π r^{2} = π 5^{2} = 78.54 square feet.

At 1/2 a gallon per square foot that's

78.54/2 = 39.27 gallons.

Penny

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