statistics

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mean = 60 wpm
standard deviation= 15 wpm

a.What is the probability that a randomly selected typist's net rate is at most 60 wpm? less than 60 wpm?

b. What is the probability that a randomly selected is between 45 and 90 wpm?

  • statistics -

    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.

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