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Standard Deviation Question

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by paulee » Tue Apr 27, 2010 3:25 am
The mean and standard deviation of the 8 numbers shown below are 10 and 0.3 respectively. What percent of the 8 numbers are within 1 standard deviation of the mean?

The 8 numbers are: 9.4, 9.9, 9.9, 9.9, 10.0, 10.2, 10.2, 10.5
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by iamseer » Tue Apr 27, 2010 3:30 am
IMO 75%

within one std. deviation of mean = within +/- 0.3 of 10

Let me know.
Thanks.
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by sanju09 » Tue Apr 27, 2010 3:34 am
paulee wrote:The mean and standard deviation of the 8 numbers shown below are 10 and 0.3 respectively. What percent of the 8 numbers are within 1 standard deviation of the mean?

The 8 numbers are: 9.4, 9.9, 9.9, 9.9, 10.0, 10.2, 10.2, 10.5
Within one standard deviation of the mean is the range for some x such that

10 - 0.3 < x < 10 + 0.3

That is 9.7 < x < 10.3

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