The restaurant manager is testing the bartender's ability to pour 45 mL of spirits correctly into a mixed drink. The manager has the bartender pour water into 12 shot glasses to test their ability to pour the correct amount of spirits:

48	45	44	43	46	47
42	46	47	45	47	49

Note: The data appears to be approximately normally distributed.

Test the bartender's ability to pour 45 mL at the 20% level of significance.

T-Distribution Table

a. Calculate the sample mean and standard deviation.

x=

Round to three decimal places if necessary

s=

Round to three decimal places if necessary

b. Calculate the test statistic.

t=

Round to three decimal places if necessary

c. Determine the critical value(s) for the hypothesis test.

• +

Round to three decimal places if necessary

d. Conclude whether to reject the null hypothesis or not based on the test statistic.

Reject

Fail to Reject