One of the two fire stations in a certain town responds to calls in the northern half of the town, and the other fire station responds to calls in the southern half of the town. One of the town council members believes that the two fire stations have different mean response times. Response time is measured by the difference between the time an emergency call comes into the fire station and the time the first fire truck arrives at the scene of the fire. Data were collected to investigate whether the council member's belief is correct. A random sample of 50 calls selected from the northern fire station had a mean response time of 4.3 minutes with a standard deviation of 3.7 minutes. A random sample of 50 calls selected from the southern fire station had a mean response time of 5.3 minutes with a standard deviation of 3.2 minutes. (a) Construct and interpret a 95 percent confidence interval for the difference in mean response times between the two fire stations. (b) Does the confidence interval in part (a) support the council member's belief that the two fire stations have different mean response times? Explain.
Added by Kim R.
Step 1
For the northern fire station, we have: - Sample size: $n_1 = 50$ - Sample mean: $\bar{x}_1 = 4.3$ - Sample standard deviation: $s_1 = 3.7$ For the southern fire station, we have: - Sample size: $n_2 = 50$ - Sample mean: $\bar{x}_2 = 5.3$ - Sample standard Show moreā¦
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