The average length of time it takes for a coolsculpting session is 25.0 minutes. Suppose a researcher wanted to test this claim. Assume that freezing times are normally distributed. The researcher collects coolsculpting data from 30 patients. He finds that the sample average is 23.5 minutes with a sample standard deviation of 2.75 minutes. Using the confidence interval approach and =0.05, does the researcher have sufficient evidence to conclude that the average time it takes to coolsculpt is less than the 25 minutes?

***coolsculpting is burning body fat with cold temperatures***