Mean and distribution .

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Mean and distribution .

by Md.Nazrul Islam » Wed Apr 04, 2012 7:52 pm
A certain characteristic in a large population has distribution that symmetric about mean .If 68 percent of the distribution lies within one standard deviation 'd' of the mean .what of the distribution is less than m+d ?

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by Bill@VeritasPrep » Wed Apr 04, 2012 8:17 pm
If 68% is between m - d and m + d, that leaves 32% to be outside of that range. Since it's a symmetric distribution, that means 16% below m - d and 16% above m + d.

Thus, 84% of the distribution is below m + d.
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