# math

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what is the exact circumference of a circle with a diameter of 13 inches?

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what is the formula PI*diameter=Cicumference used for?

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i am confused??

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the pi is 3.14

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C=PI*diameter.

You need to get this down.

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okay but the options i have to choose from are:

a. 26Pi in.
b. 6.5Pi in.
c. 13Pi in.
d. 42.25Pi in.
e. 169Pi in.

i think it's a. right?

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