A sample of grocery store receipts has a mean of 157 and a s

A sample of grocery store receipts has a mean of $157 and a standard error of the mean of $4.77. Your job is to decide whether or not the mean of sales at this grocery store is different from $150.

The symbol alpha represents the significance level for this test, and typically equals .05. This means that we have a ___% chance of committing Type I Error.

Solution

The significance level is, by definition, the probability of committing a type I error.

Thus, there are 5% chance of committing a type I error. [ANSWER: 5%]