Brent checks the sales records for a random sample of 16 days and finds the mean number of gallons sold is 150 gallons per day; the sample standard deviation is 12 gallons. With 95% confidence, estimate the what is mean number of gallons that Brent should stock daily.

[143.61, 156.39]

Step-by-step explanation:

Because the population standard deviation is not available AND the sample size is less than 31, we can use a t procedure here.

Plug these values into your calculator:

Sample mean = 150

Sample size = 16

Standard deviation = 12

Confidence level = 95% = 0.95

and get [143.61, 156.39] as your confidence interval