Question

MULTIPLE CHOICE (12 1.5 points) 1. A 90% tobo 98.6 to 118.4. If the couldence level is chang«I to95%, the cualiden" interval tr μ a. Becomes wider b. Remains unchanged c. Becomes narrower d. None of the above answers are correct 2. If the width of a confidence interval for μ is too narrow when the population standard deviation σ is known, which one of the following is the best action to increase the interval width? a. Reduce the sample size n b. Reduce the population standard deviation ơ c. Increase the confidence level d. Increase the sample size n e. None of the above answers are correct. 3. Which of the following expressions are true about a large-sample population mean μ ? e. None of the above answers are correct. 4. In developing a confidence interval for the population mean, a sample of 50 observations was and the confidence interval was 15.24 interval would have been used, 1.20. Had the sample size been 800 instead of 50, the confidence a. 3.81 +1.20 b. 7.62+1.20 c. 15.24 0.30 d. 15.24±0.60 e. None of the above answers are correct. 14

Answer 1

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