Question

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.

x̄ = x̄ =

Round to three decimal places if necessary

s=s=

Round to three decimal places if necessary

b. Calculate the test statistic.

t=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

Answer 1

a)

x = 45.750
s = 2.050

b)

Test statistic,
t = (xbar - mu)/(s/sqrt(n))
t = (45.75 - 45)/(2.05/sqrt(12))
t = 1.267

c)

Critical value of t are -1.363 and 1.363.

d)

Fail to Reject