1)Express the confidence interval 38.4%5.8%38.4%5.8% in interval form. Express the answer in decimal format (do not enter as percents).

2)We wish to estimate what percent of adult residents in a certain county are parents. Out of 400 adult residents sampled, 336 had kids. Based on this, construct a 90% confidence interval for the proportion, p, of adult residents who are parents in this county. Give your answers as decimals, to three places. < p <

3)Assume that a sample is used to estimate a population proportionp. Find the margin of errorM.E. that corresponds to a sample of size 162 with 24.1% successes at a confidence level of 99.8%. M.E. = % Answer should be obtained without any preliminary rounding. However, the critical value may be rounded to 3 decimal places. Round final answer to one decimal place

4)Giving a test to a group of students, the grades and gender are summarized below

A B C Total

Male 18 10 11 39

Female 7 4 13 24

Total 25 14 24 63

Let represent the percentage of all male students who would receive a grade of B on this test. Use a 85% confidence interval to estimate p to three decimal places.

Enter your answer as a tri-linear inequality using decimals (not percents).

< p <

5)A political candidate has asked you to conduct a poll to determine what percentage of people support her.

If the candidate only wants a 8% margin of error at a 99% confidence level, what size of sample is needed?

Give your answer in whole people.