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Thank you We sneak here's a question for you Don't

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forget to whistle while you shmoop all right The entire

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graduating class at newton high school was pulled to see

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how far away from home the students would be attending

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college The mean number of miles they were from home

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is two hundred ten and the standard deviation of miles

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is twenty three If mariana z score is negative one

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point three how many miles away from home does she

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attend college and hear the potential answers Okay so we're

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given the mean number of miles away from home and

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standard deviation and that mariana's e score is negative One

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point three So what does z score even mean in

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statistics A z score is a measurement of a scores

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relationship to the meet In this context the sea score

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gives a relationship between the number of miles mariana is

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away from home and the mean number of miles newton

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high school students are away from home at that art

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is a score of zero means that mariana is the

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same number of miles away from home as the mean

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two hundred ten A negative c score mean she is

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Less than two hundred ten miles away and a positive

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one means that she's greater than two hundred ten miles

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away All right we're given that her z score is

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negative one point three so we know she must be

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less than two hundred ten miles away which eliminates a

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box Now to find out exactly how far she is

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away well let's put out our handy dandy z score

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Formula c equals x minus mu over sigma where x

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is mary honest distance from home New is the population

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mean and sigma is the population standard deviation now as

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we just plug stuff in well z is negative one

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point three two hundred ten is mu and twenty three

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has sigma We can multiply both sides by twenty three

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and add two hundred ten to both sides and we

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get that x equals one hundred eighty point one miles

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So ex tells us that mariana is living one hundred

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eighty point one miles away from home Answer c true

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