A cruise company would like to estimate the average beer consumption to plan its beer inventory levels on future seven-day cruises. (The ship certainly doesn't want to run out of beer in the middle of the ocean!) The average beer consumption over 16 randomly selected seven-day cruises was 81,771 bottles with a sample standard deviation of

4,521 bottles.

Construct an 80% confidence interval to estimate the average beer consumption per cruise.

Thanks.