The margarita is one of the most common tequila-based cocktails, made with tequila, triple sec, and

The margarita is one of the most common tequila-based cocktails, made with tequila, triple sec, and lime
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