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For a good time solve this shmoopy question...

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A sphere has a volume of 288pi inches cubed.

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What is the radius of the sphere?

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And here are your options...

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Alright, the key thing we have to know...

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is the radius from the center of the Earth to the crispy crust.

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That's R. That formula: four-thirds times quantity pi R cubed.

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We just need to solve for R. So for starters...

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multiply both sides by three-fourths and we have pi R cubed

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equals three-fourths times 288 pi. Rewrite the equation

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as pi R cubed equals 216 pi

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and we can get rid of the pi on both sides by dividing it out and we're left

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with R equals the cube root of 216.

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So the answer is 6 and yeah, 216 is a way out their number

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so you can just started by multiplying out three times three to get nine times

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three with just 27. Too low. Then try four

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and five and you have found your way to six pretty quick.

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Anyway, the answer is R equals 6 or answer C.

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