I took a sample of 20 students at St. Kate’s and measured their heights. I computed...

I took a sample of 20 students at St. Kate’s and measured their heights. I computed the sample mean (x bar) and want to construct a confidence interval. I want to create an approximate 95% confidence interval. What is this?

I took a sample of 20 students and recorded their height. X bar (sample mean) was 63 inches. The population standard deviation for height is 4 inches. What is the approximate 95% confidence interval?

A 99% confidence interval will always be wider than a 95% confidence interval. True or false?

When will x bar (sample mean) be distributed approximately normally?

I take a 30 person sample of heights from St. Kate’s students and calculated x bar. I want to construct a 90% confidence interval. What z value should I use?

Expert Solution

orchestra answered 2 years ago

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