The commute times for the workers in a city are normally distributed with an unknown population mean and standard deviation. If a random sample of 27 workers is taken and results in a sample mean of 22 minutes and sample deviation of 3 minutes, find a 95% confidence interval estimate for the population mean using the Student's t-distribution.
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The commute times for the workers in a city are
df | t0.10 | t0.05 | t0.025 | t0.01 | t0.005 |
---|---|---|---|---|---|
... | ... | ... | ... | ... | ... |
25 | 1.316 | 1.708 | 2.060 | 2.485 | 2.787 |
26 | 1.315 | 1.706 | 2.056 | 2.479 | 2.779 |
27 | 1.314 | 1.703 | 2.052 | 2.473 | 2.771 |
28 | 1.313 | 1.701 | 2.048 | 2.467 | 2.763 |
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