a. Describe in your own words, what it means to find a "confidence interval around μ"? b. Suppose we took a preliminary sample of 45 students at FIT who work and found their sample average to be $32.40 per hour with a sample standard deviation of $8.62. i. Construct an 88% confidence interval for μ. c. Suppose we took another sample of only 17 different students and found their average hourly rate to be $24.50 and the sample standard deviation to be $4.80. Construct a 96% confidence interval for μ. Assume a normal population.
Added by Lorena J.
Step 1
40 Sample standard deviation (s) = $8.62 Sample size (n) = 45 Critical value (t*) for 88% confidence level = 1.555 Calculate the margin of error (ME): ME = t* * (s / √n) ME = 1.555 * (8.62 / √45) ME ≈ 1.285 Calculate the confidence interval: Lower limit = x̄ - Show more…
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