# Math/Statistics

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A statistics teacher believes that the final exam grade for her elementary stats class have a normal distribution with a mean of 82 and a standard deviation on 8.
Find the score which separates the top 10% of the scores from the lowest 90% of the scores.

• Math/Statistics -

z-score for 90
= (90-82)/8 = 1

so don't even have to go to tables or charts, we are 1 standard deviation from 82, so
a score of 90 will do it

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