Question

A population has standard deviation - 17.3. Part 1 of 2 (a) How large a sample must be drawn so that a 99.9% confidence interval for ji will have a margin of error equal to 3.7? Round the answer up to the nearest integer. (Round the critical value to no less than three decimal places.) A sample size of is needed to be drawn in order to obtain a 99.9% confidence interval with a margin of error equal to 3.7. Part 2 of 2 (b) if the required confidence level were 90%, would the necessary sample size be larger or smaller? (Choose one) , because the confidence level is (Choose one) .

Answer 1

al lasi Margin of enor = Z E Jn New z value Z value for 99.9% confidence intewal is 3.291 0 Margin - 17.3. of enor = 3.7. .7= 3.291 X 17.3 (n = 3,291 X 17.3 3.7 in= 1513876 n = 236.7797. Nearest integer Mence, sample size sample size as 237. of 237 is needed .- Anila), Now, (6) for As margin of enor confidence level 7 -value also will lead to constant, decreases from 99.9% decreasts. to 90%. This Hence, smaller decuases in sample size. sample size would be regured - Ans (6)

Answer 2

im don't sure how to do that math problem