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.

asked by John
  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
  2. Arceilts like this just make me want to visit your website even more.

    posted by LGYUkKOl

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