Normal distribution

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Golden313
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#1
Report Thread starter 1 month ago
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Help me please.. The mass of letters are normally distributed with mean 15g. 92 percent of the letters are within 10g of the mean. Calculate the standard deviation
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the bear
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#2
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so you can see that 8 % are more than 10g from the mean. because of the symmetry of the curve you can say that 4% are more than a certain number of grams.
then you can look up a relevant z value.
after that just use the relation

z = { X - µ } / σ

to work out σ
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