juice, often served with salt on the glass rim. A manager at a local bar is concerned that the bartender is

not using the correct amounts of the three ingredients in more than 50% of margaritas. He secretly

observed the bartender and found that he used the CORRECT amounts in only 9 out of the 39

margaritas in the sample. Use the critical value approach to test if the manager's suspicion is justified

at α = 0.10. Let p represent the proportion of all margaritas made by the bartender that have

INCORRECT amounts of the three ingredients. Use Table 1.

a. Select the null and the alternative hypotheses.

**H0: p ≤ 0.50; HA: p > 0.50**

b. Calculate the sample proportion. (Round your answer to 3 decimal places.)

9/39 =

**0.231**

c. Calculate the value of test statistic. (Round your intermediate calculations to 4 decimal places and final answer to 2 decimal places.)

Using our proportion hypothesis calculator, we get:

**Test Stat = -3.36**

d. Calculate the critical value. (Round your answer to 2 decimal places.)

Using the link above, we get a critical value of

**1.2816**

e. What is the conclusion?

**The manager’s suspicion is not justified since the value of the test statistic does not fall in the rejection region. Do not reject H0**