## Answer

###### Wiki User

###### 01/05/2012

Area of a circle = pi*radius2 measured out in square units

for pi use this number 3.14159

and remember the radius of a circle = half the diameter.

----------------------------------------------------------------

Thus a circle with a 10 inch diameter would have an area of:

Radius = diamiter/2, which is 10/2= 5

3.14159 * (5*5) = **78.53975 square inches**

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