The number of cars sold annually by used car salespeople is normally distributed with a standard deviation of 15. A random sample of 15 salespeople was taken, and the number of cars each sold is listed here. find the 95% confidence interval estimate of the population mean. Interpret the interval estimate. 79 43 58 66 101 63 79 33 58 71 60 101 74 55 88
Added by Michael S.
Step 1
The sample mean (x̄) is the sum of all the values divided by the number of values. In this case, the sum of all the values is 1030 and the number of values is 15. So, x̄ = 1030 / 15 = 68.67 (rounded to two decimal places). The standard error (SE) is the Show more…
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Inference for Quantitative Data: Means
Quiz 27
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