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statistics

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The mean lifetime of a sample of 100 light tubes is 1570 hours with a standard deviation of 80 hours test the hypothesis that the mean lifetime of the tubes is 1600 hours

  • statistics -

    Z = (score-mean)/SEm

    SEm = SD/√n

    Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability of the Z score.

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