Here are summary stastistics for randomly selected weights of newborn girls: n=224,overline{x}=28.3 text{hg},s=7.1 text{hg}. Construct a confidence interval estima

Khaleesi Herbert

Khaleesi Herbert

Answered question

2020-11-07

Here are summary stastistics for randomly selected weights of newborn girls: n=224,x=28.3hg,s=7.1hg. Construct a confidence interval estimate of mean. Use a 98% confidence level. Are these results very different from the confidence interval 26.5hg<μ<30.7hg with only 14 sample values, x=28.6 hg, and s=2.9 hg? What is the confidence interval for the population mean μ?

 27,2 hg<μ<29,4 hg? (Round to one decimal place as needed).

Are the results between the two confidence intervals very different?

Answer & Explanation

Bentley Leach

Bentley Leach

Skilled2020-11-08Added 109 answers

Step 1 From the provided information, Sample size (n)=244 Sample mean (x)=28.3 hg Sample standard deviation (s)=7.1 hg Step 2 Since, the population standard deviation is unknown, therefore, the t distribution will be used. Confidence level = 98% Level of significance (α)=10.98=0.02 The degree of freedom =n1=2441=243 The critical value of t at 243 degree of freedom with 0.01 level of significance from the t value table is 2.34. Step 3 The required 98% confidence interval can be obtained as: CI=x±tα2,n1sn
=28.3±(2.34)7.1224
=28.3±1.1
=(27.2,29.4) Thus, the confidence interval is 27.2<μ<29.4. No, the results between the two confidence intervals are not very different. The confidence interval limits are almost similar.

Do you have a similar question?

Recalculate according to your conditions!

New Questions in College Statistics

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?