Question

Here are summary statistics for randomly selected weights of newborn girls: n=229, x = 33.2 hg, s = 7.3 hg. Construct a confidence interval estimate of the mean. Use a 90% confidence level. Are these results very different from the confidence interval 31.9 hg< <34.7 hg with only 14 sample values, x= 33.3 hg, and s = 2.9 hg? What is the confidence interval for the population mean u? ng<u< ng (Round to one decimal place as needed.) Are the results between the two confidence intervals very different? O A. Yes, because one confidence interval does not contain the mean of the other confidence interval. O B . Yes, because the confidence interval limits are not similar. O C. No, because each confidence interval contains the mean of the other confidence interval. O D. No, because the confidence interval limits are similar.

Answer 1

(ok, +8 - x) = 15

The critical t-value for α=0.1 and df=228 degrees of freedom is tc​=1.652.

CI = (33.2 - 1.652.3.7.3, 33.2 + 1.652,x.7.3). V229 = (33.2 - 0.797, 33.2 +0.797) = (32.403, 33.997)

Yes, because the confidence interval limits are not similar