# Math

The mean time to complete a certain stat quiz is 25 minutes, with a standard deviation of 5 minutes. Find the probability of a student taking.
1.) less than 15 minutes.
2.) Between 15 and 25 minutes.
3.)more than 25 minutes.

1. Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions/probabilities related to the Z scores.

posted by PsyDAG
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posted by LGYUkKOl

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