# statistics

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The reaction time of subjects to a certain psychological experiment is considered to be normally distributed with a mean of 20 seconds and a standard deviation of 4 seconds. What is the reaction time such that only 10% of subjects are faster?

• statistics -

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion (.10) related to the Z score. Insert Z score in equation above and solve for the score.

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