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Volume with PI math problem. We are looking at number three. It says how many square inches of crest would it take to cover the bottom of the pie dish with a 15 inch diameter.

Volume with PI math problem. We are looking at number three. It says how many square-example-1

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3) The area of a circle is:


A=\pi r^2

so if the diameter is 15 then we know that the radius is 7.5 so the area will be:


\begin{gathered} A=3.14\cdot7.5^2 \\ A=176.6 \end{gathered}

4) the distance around is the perimeter and the perimeter of a circle is:


D=2\pi r

So in this case the radius is 10 so:


\begin{gathered} D=2\cdot3.14\cdot10 \\ D=60.28 \end{gathered}

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