# statistics

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The times taken to complete a statistics test by all students are normally distributed with a mean of 120 minutes and a standard deviation of 12 minutes. Find the probability that the mean time taken to complete this test by a random sample of 16 students would be between 122 and 125 minutes.

• statistics -

Z = (score-mean)/SEm(Standard Error of the mean)

SEm = SD/√n

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

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