# Math

a random sample of 28 patients across the country had an average cost of 5250 with a standard deviation of 629.at a= 0.025 can it be concluded that the mean is less than 5400

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1. 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 (.025) related to the Z score.

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