# Statistics: Normal Distribution Question

Hi, I need an explanation on how to solve this? I really do not understand these concepts.

Question: The average customer waiting time at a fast food restaurant has been 7.5 minutes. The customer waiting time has a normal distribution. The manager installs a new system and checks if the use of the new system will decrease average customer waiting time in the store.

1) What are the null and alternative hypotheses for this scenario?

2) Suppose the population standard deviation was known. At a significance level of 0.05, what is the rejection point condition? We would reject the null hypothesis if?

3) Based on a random sample of 36 customer transactions, the mean waiting time is 6.3 minutes and the sample standard deviation is 3 minutes per customer. What is the value of the Observed test statistic?

https://brainmass.com/statistics/normal-distribution/statistics-normal-distribution-question-508951

#### Solution Preview

1) Let mu be the true mean waiting time at a fast food restaurant. Since the average customer waiting time at a fast food restaurant has been 7.5 minutes and we are testing if the use of the new system will decrease average customer waiting time in the store, the null and ...

#### Solution Summary

Statistics for normal distributions are examined.