# GED Math 5.5 Measurement

GED Math 5.5 Measurement. What is the approximate radius of the cone?

 3D Geometry Area and VolumeSurface Area Area and Volume AreaVolume GED Math Measurement Geometry 3D GeometryArea and Volume Language English Language Skill Area 2 Measurement (Quantitative)

### Transcript

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the approximate radius of the cone A horrible question That

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and here the potential answers Well another formula question coming

00:27

right at you So those questions looking for the radius

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of the cone but really we need to work backwards

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and figure out how someone might arrive it this volume

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Well we've got the height of the cone and the

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volume so let's blood those into our cone volume formula

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which is volume equals one third pi r squared times

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type that's the formula Well you know what we know

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We get a thousand five point Three cubic feet equals

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one thirds pi r squared times fifteen And the radius

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of the peace we're looking for is we need to

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isolate it And isolation can be good Go to your

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happy place part So let's Just multiply both sides by

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three to get rid of the one third that gives

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Us three thousand fifteen point nine equals pi r squared

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times fifteen Great now let's Divide both sides by fifteen

01:13

pie and we get three thousand fifteen point nine over

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fifteen pie with peoples are squared well now before we

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go any further we kind of need to deal with

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this mess on the left hand side so let's see

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what our calculators can do with it Fifteen pies right

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around forty seven point one two and note that the

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question did ask for an approximate value so we don't

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have to be exactly pot here Well we have three

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thousand fifteen point nine divided by about forty seven point

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one two and it's roughly sixty four almost on the

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dot Actually the last step We take the square root

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of both sides and our equals broke a six four

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which is eight Answer b Now we just have to

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look into our happy place on the mountain and see 00:01:54.232 --> [endTime] if we came up with the same