The owner of a local supermarket wants to estimate the difference between the average number of gallons of milk sold per day on weekdays and weekends. The owner samples 21 weekdays and finds an average of 291.791 gallons of milk sold on those days with a standard deviation of 37.284. 28 Saturdays and Sundays are sampled and the average number of gallons sold is 383.274 with a standard deviation of 47.373. If a 90% confidence interval is calculated to estimate the difference between the average number of gallons sold on weekdays and weekends, what is the margin of error? Assume both population standard deviations are equal.

Question 7 options:

1)

21.006

2)

20.592

3)

16.273

4)

1.67792672

5)

12.51916004