A random sample of 49 observations was taken. The average in the sample was 90 with a variance of 400. a. Construct a 98% confidence interval for μ. b. Construct a 99% confidence interval for μ. c. Discuss why the 98% and 99% confidence intervals are different. d. What would you expect to happen to the confidence interval in Part a if the sample size was increased? Explain your answer with details
Added by Silvia G.
Step 1
We are given the sample size (n = 49), sample mean (x̄ = 90), and sample variance (s² = 400). We can find the sample standard deviation (s) by taking the square root of the variance: s = √400 = 20. Show more…
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