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In: Statistics and Probability

777 We selected a random sample of n = 50 male adults. The sample men produced...

777

We selected a random sample of n = 50 male adults. The sample men produced an average of x = 542 grams of fat per day with a standard deviation of s = 13.6 grams of fat per day. Based on this sample, construct a 95% confidence interval for the mean daily production of fat for the men.

Then find 99% CI and compare to the 95% CI.

Solutions

Expert Solution

Given :

Since population standard deviation is unknown ( not given ) , we need to use t-interval.

The formula is ,

First we need to find the 95% confidence interval ,

So c = 0.95

Degrees of freedom = n - 1 = 50 - 1 = 49

Using excel function ,

Now plug the values in the formula ,

Therefore the 95% confidence interval for the mean daily production of fat for the men is ( 538.1341 , 545.8659 )

---

Now we need to find the 99% confidence interval ,

c = 0.99

df = 49

Usinge excel function ,

Now plug the values in the formula ,

Therefore the 99% confidence interval for the mean daily production of fat for the men is ( 536.8455 , 547.1545 )

The 99% confidence interval for the mean daily production of fat for the men is wider than the 95% confidence interval for the mean daily production of fat for the men .

orchestra answered 1 year ago

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