ShmoopTube

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All right sy shmoop there's Another one for you If

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the area of a circular cookie is fifteen point nine

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square inches while big cookie how much does it measure

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across Yeah That's A texas size cookie Okay well cookies

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The perfect canvas for math problems That's Because cookies are

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the perfect consolation prize for a wrong solution And the

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perfect prize for a correct solution Yeah win win Anyway

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this example asked us to find the diameter of the

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cookie with a given area There's no formula that links

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the area of a circle directly to its diameter But

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there is another way here Use the formula for the

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area of a circle Find the radius and then double

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it So let's start by finding the radius a equals

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pi r squared Remember that's the formula there So they

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give us a lot of this fifteen point nine square

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inches is pi r squared or well we can divide

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out pie on both sides That gets us a five

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in change and inches there for r squared Take square

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root of five point o six and we get a

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two point two five inches as the radius Well now

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that we have the radius the cookie find the diameter

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by just multiplying it by two And that gets us

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You have four and a half inches So that's what

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This Cookie measures The answer is d and we're schmuck 00:01:14.031 --> [endTime] because we eat our cookies Thank you very much

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