Answer:
The mean waiting time of all customers is significantly more than 3 minutes, at 0.05 significant level
Step-by-step explanation:
Step 1: State the hypothesis and identify the claim.
[tex]H_0:\mu=3\\H_1:\mu\:>\:3(claim)[/tex]
Step 2: We calculate the critical value. Since we were not given any significant level, we assume [tex]\alpha=0.05[/tex], and since this is a right tailed test, the critical value is z=1.65
Step 3: Calculate the test statistic.
[tex]Z=\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }=\frac{3.1-3}{\frac{0.5}{\sqrt{100} } }=2[/tex]
Step 4:Decide. Since the test statistic , 2 s greater than the critical value, 1.65, and it is in the critical region, the decision is to reject the null hypothesis.
Step 5: Conclusion, there is enough evidence to support the claim that the mean is greater than 3
