1. Rangers took a random sample of live aspen trees and measured the base circumference of...

1. Rangers took a random sample of live aspen trees and measured the base circumference of each tree. The sample had 50 trees with a mean circumference of 15.57 inches.

a. Find a 95% confidence interval for the population mean base circumference of all aspen trees in Roosevelt National Forest. Assume that the population standard deviation is 4.78 inches. You must show work for full credit.

b. Would the 90% confidence interval for the population mean base circumference of aspen trees be wider or narrower than the 95% confidence interval you found in part A? Explain.

please show complete work, thank you

Expert Solution

orchestra answered 2 years ago

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