Question

Here are summary statistics for randomly selected weights of newborn girls: n=196, x=26.2 hg, s=6.2 hg. Construct a confidence interval estimate of the mean. Use a 99% confidence level. Are these results very different from the confidence interval 24.8 hg<μ<27.4 hg with only 19 sample values, x=26.1 hg, and s=1.9 hg?A. What is the confidence interval for the population μ mean ?___hg<μ<___hg (Round to one decimal place as needed) Are the results between the two confidence intervals very different?A.)No, because the confidence interval limits are similar.B.)Yes, because the confidence interval limits are not similar.C.)Yes, because one confidence interval does not contain the mean of the other confidence interval.D.)No, because each confidence interval contains the mean of the other confidence interval.

Answer 1

n=196

x=26,2

s=6,2

CL=99%

then z= 2.576

we use the following formula to find the confidence interval

$CI=x\pm z\frac{s}{\sqrt{n}}$$CI=26.2\pm2.576\frac{6.2}{\sqrt{196}}$$CI1=27.34$$CI2=25.059$$25.1<\mu<27.3$

Thus the 1st answer is: 25.1 < u < 27.3

now comparing the 2 intervals we find the answer to the second question

Are the results very differts?

the answers is

A. No, because the confidence interval limits are similar