Q: You don't have a population standard deviation but you have sample data. find out a sample mean and standard deviation and use the sample standard deviation value to complete the inferential test. And the sample size is < 30 so this uses a students t test. ( uses the same 5 steps as does a Z test but you have a different method of finding the critical value

A friend of mine works part-time as a waitress. Recently a local mid-scale restaurant tried to hired her telling her that she would average 75$ a night in tips. So she started work there and for 15 (n = 15) random days collected her tip money. Below is the data. Test at the 0.05 alpha, 1 tail test to determine if they told her the truth, or did she make less or more statistically?

Data : 62, 83, 78, 91, 69, 73, 79, 82, 50, 79, 81, 79, 71, 79, 75