Sale of Microwaves
The average number of microwaves sold in the city in 2015 was 2700 per day. Suppose the standard deviation is 1551 and the distribution is right-skewed.
Suppose we take a random sample of 121 days in the year. We want to find the probability that the sample mean will be more than 141 units away from the population mean. The TI-84 output is shown.
![1897_Sale of Microwaves.png](https://secure.tutorsglobe.com/CMSImages/1897_Sale of Microwaves.png)
a. Why is the distribution Normal and not right-skewed like the population?
b. Why is the z-score 1?
c. What is the probability that the sample mean will be more than 141 units away from the population mean?