<PRE><B>Question 340795</B>
I assume that 40&#39; (or 40 feet) applies to the circumference of the circle since you di dnot point this out in your question.

Use C = 2pir

Let C = 40 and solve for r

Let pi = 3.14


40 = 2(3.14)r

40 = 6.28r

40/6.28 = r

6.4 = r

NOTE:  I rounded 6.369 to the nearest tenths to get the radius answer of 6.4 for your circle.

Make sense?

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