Answer :
To solve this problem, we'll go through the steps provided and understand the results derived from the problem statement. We are comparing waiting times from two different setups at an inspection station: a single waiting line and two waiting lines. Here's how to interpret the problem:
### Part (a): Hypothesis Testing
1. Hypotheses:
- Null Hypothesis ([tex]\(H_0\)[/tex]): The means of the two populations ([tex]\(\mu_1\)[/tex] and [tex]\(\mu_2\)[/tex]) are equal ([tex]\(\mu_1 = \mu_2\)[/tex]).
- Alternative Hypothesis ([tex]\(H_1\)[/tex]): The means of the two populations are not equal ([tex]\(\mu_1 \neq \mu_2\)[/tex]).
2. Test Statistic:
- The test statistic calculated is approximately [tex]\(t = 0.16\)[/tex]. This statistic measures the standardized difference between the means of the two samples.
3. P-value:
- The P-value found is approximately [tex]\(0.874\)[/tex]. The P-value helps us determine the strength of the evidence against the null hypothesis.
4. Conclusion:
- We typically set a significance level (commonly 0.05 for 95% confidence) to decide whether to reject the null hypothesis.
- Since the P-value is [tex]\(0.874\)[/tex], which is greater than the significance level of 0.05, we fail to reject the null hypothesis.
- Conclusion: There is not enough evidence to conclude that the waiting times for a single line are different from two waiting lines.
### Part (b): Confidence Interval
1. Confidence Interval for the Difference in Means ([tex]\(\mu_1 - \mu_2\)[/tex]):
- A 95% confidence interval for the difference in means is calculated to further interpret the results.
- The confidence interval is: [tex]\(-140.5 < \mu_1 - \mu_2 < 165.4\)[/tex].
2. Interpretation of the Confidence Interval:
- This interval includes zero, suggesting that there is no significant difference in the average waiting times between the two setups.
By going through these steps, we've analyzed the waiting time data to understand the differences (or lack thereof) between having a single line versus two lines at an inspection station.
### Part (a): Hypothesis Testing
1. Hypotheses:
- Null Hypothesis ([tex]\(H_0\)[/tex]): The means of the two populations ([tex]\(\mu_1\)[/tex] and [tex]\(\mu_2\)[/tex]) are equal ([tex]\(\mu_1 = \mu_2\)[/tex]).
- Alternative Hypothesis ([tex]\(H_1\)[/tex]): The means of the two populations are not equal ([tex]\(\mu_1 \neq \mu_2\)[/tex]).
2. Test Statistic:
- The test statistic calculated is approximately [tex]\(t = 0.16\)[/tex]. This statistic measures the standardized difference between the means of the two samples.
3. P-value:
- The P-value found is approximately [tex]\(0.874\)[/tex]. The P-value helps us determine the strength of the evidence against the null hypothesis.
4. Conclusion:
- We typically set a significance level (commonly 0.05 for 95% confidence) to decide whether to reject the null hypothesis.
- Since the P-value is [tex]\(0.874\)[/tex], which is greater than the significance level of 0.05, we fail to reject the null hypothesis.
- Conclusion: There is not enough evidence to conclude that the waiting times for a single line are different from two waiting lines.
### Part (b): Confidence Interval
1. Confidence Interval for the Difference in Means ([tex]\(\mu_1 - \mu_2\)[/tex]):
- A 95% confidence interval for the difference in means is calculated to further interpret the results.
- The confidence interval is: [tex]\(-140.5 < \mu_1 - \mu_2 < 165.4\)[/tex].
2. Interpretation of the Confidence Interval:
- This interval includes zero, suggesting that there is no significant difference in the average waiting times between the two setups.
By going through these steps, we've analyzed the waiting time data to understand the differences (or lack thereof) between having a single line versus two lines at an inspection station.