Jessica, a plant director, has 3.5 employees leaving per month, with a standard deviation of 0.4. She decided to see if using a new benefits package would affect her average. She used the new benefits...

Jessica, a plant director, has 3.5 employees leaving per month, with a standard deviation of 0.4. She decided to see if using a new benefits package would affect her average. She used the new benefits package for 15 months. For those 15 months, Jessica got an average of 3.1 employees leaving. She wants to know if the new benefits package reduced the number employees leaving per month.

She conducts a one-mean hypothesis at the 5% significance level, to see if the new benefits package caused her to get a different number of employees leaving per month.

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