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All right see math Shmoop er's We've got some standard

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deviants for you using the formula for standard deviation What

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is this find asked for the following set of data

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Okay big breath We're being asked to turn the crank

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by hand on the standard deviation machine What goes on

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inside that machine between when we dumped the numbers in

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and we get the result after turning the crank a

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few times Well the machine looks something like this and

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let's Take off the side pale and put our mitts

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on and peek inside at the guts of the machine

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All the goopy stuff way start off by finding the

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mean that's His acts with the line over it will

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some the values and divide by five So how do

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we do that We got zero eight nine thirteen fourteen

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We divide by five Forty for over five That's eight

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point eight Well now we need to take each data

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point Subtract the mean from them So that's the x

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by minus the x mean part And that gets us

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this table where we go from negative eight point eight

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and the negative point eight and then point to and

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on and on and on Okay And now we need

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to square those results So that's the ex sabai minus

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the actual apart and we get well negative eight point

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Eight and they were just squaring this thing Seventy seven

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point four and then zero point six Foreign point No

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foreign seventeen twenty seven Now we some those values that's

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the sigma part So we got seventy seven point four

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four and then point six four point oh four seventeen

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hundred all gets one twenty two point eight in total

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all right time to divide the in minus one thing

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into it which is well five minus one because that's

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what the end value is or four so that's one

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twenty two point eight divided by four that's about thirty

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point seven All we have left now is a swift

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square rooting toe pull out finally the last part of

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it So what's the square root of thirty point seven

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in texas that's about five point five four so our

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signal or standard deviation is about five point five four

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that's it The answer is c we are fully shmoop 00:02:03.53 --> [endTime] it on this one

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