Question

In: Statistics and Probability

The Hiatus retail outlet takes a random sample of 25 customers from a segment population of...

  1. The Hiatus retail outlet takes a random sample of 25 customers from a segment population of 1,000 with a mean average transaction size of $80 normally distributed with a known population standard deviation of $20 per transaction. Find The 90% confidence interval for transaction size, and The 95% confidence interval for transaction size, and The 99% confidence interval for transaction size. What do these results indicate for management?

Solutions

Expert Solution

The 90%, 95%, 99% CI are as follows

The all three confidence interval contains the mean value 80 .

Based on the confidence interval the mean average size is 80 is true.

As we go from 90%, 95%, 99% the confidence interval becomes wider.

99% CI is most wider out of them.

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