1. A student was asked to find a 99% confidence interval for the population proportion of students who take notes using data from a random sample of size n = 90. Which of the following is a correct interpretation of the interval 0.14 < p < 0.3?

Check all that are correct.

A. With 99% confidence, a randomly selected student takes notes in a proportion of their classes that is between 0.14 and 0.3.

B. There is a 99% chance that the proportion of the population is between 0.14 and 0.3.

C.The proprtion of all students who take notes is between 0.14 and 0.3, 99% of the time.

D.With 99% confidence, the proportion of all students who take notes is between 0.14 and 0.3.

E. There is a 99% chance that the proportion of notetakers in a sample of 90 students will be between 0.14 and 0.3.

2. Express the confidence interval 0.4510.0720.4510.072 in open interval form (i.e., (0.155,0.855)).___?

3.A Gallup survey based on telephone and face-to-face interviews with 4,220 adults in China, aged 15 and older suggests that 30% smoke regularly or occasionally. The following is also noted "one can say with 95% confidence that the maximum margin of sampling error is 2.5 percentage points". Which of the following is true based on the results of this survey?

a.If the sample size was larger, the margin of error would be larger as well.

b.Exactly 30% of all Chinese adults smoke.

c.We are 95% confident that 25% to 35% of all Chinese adults smoke.

d.We are 95% confident that 27.5 % to 32.5 % of all Chinese adults smoke.

e.If we were to randomly sample another group of 4,220 Chinese adults we would find that exactly 30% of them smoke as well.

4. We wish to estimate what percent of adult residents in a certain county are parents. Out of 300 adult residents sampled, 42 had kids. Based on this, construct a 99% confidence interval for the proportion p of adult residents who are parents in this county. Express your answer in tri-inequality form. Give your answers as decimals, to three places. ____? < p < ____? Express the same answer using the point estimate and margin of error. Give your answers as decimals, to three places. p = ____ ? _______?

5. A psychologist is interested in constructing a 99% confidence interval for the proportion of people who accept the theory that a person's spirit is no more than the complicated network of neurons in the brain. 67 of the 718 randomly selected people who were surveyed agreed with this theory. Round answers to 4 decimal places where possible.

a. With 99% confidence the proportion of all people who accept the theory that a person's spirit is no more than the complicated network of neurons in the brain is between___?and___ ?.

b. If many groups of 718 randomly selected people are surveyed, then a different confidence interval would be produced from each group. About ______ percent? of these confidence intervals will contain the true population proportion of all people who accept the theory that a person's spirit is no more than the complicated network of neurons in the brain and about____ percent ?will not contain the true population proportion.

6. Out of 100 people sampled, 33 had kids. Based on this, construct a 95% confidence interval for the true population proportion of people with kids. Give your answers as decimals, to four places _____?< p < ______?

7.Assume that a sample is used to estimate a population proportion p. Find the 95% confidence interval for a sample of size 371 with 106 successes. Enter your answer as an open-interval (i.e., parentheses) using decimals (not percents) accurate to three decimal places.

C.I. =______

8.If n = 120 and X = 96, construct a 99% confidence interval for the population proportion, p. Give your answers to three decimals ___? < p <____?

9.You want to obtain a sample to estimate a population proportion. At this point in time, you have no reasonable preliminary estimation for the population proportion. You would like to be 98% confident that you estimate is within 4.5% of the true population proportion. How large of a sample size is required?

n = ______

10.A political candidate has asked you to conduct a poll to determine what percentage of people support him. If the candidate only wants a 2% margin of error at a 95% confidence level, what size of sample is needed? When finding the z-value, round it to four decimal places.____?