According to the latest financial reports from a sporting goods store, the mean sales per customer was $75 with a population standard deviation of $6. The store manager believes 39 randomly selected customers spent more per transaction. What is the probability that the sample mean of sales per customer is between $76 and $77 dollars? You may use a calculator or the portion of the z -table given below. Round your answer to two decimal places if necessary.
Added by Angela H.
Step 1
The standard error of the mean is the standard deviation divided by the square root of the sample size. In this case, the standard deviation is $6 and the sample size is 39. So, the standard error of the mean is $6 / sqrt(39) = $0.96 approximately. Show more…
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