1. Out of 400 people sampled, 76 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 three places

_______________ < p <_____________

2. Assume that a sample is used to estimate a population proportionp. Find the 99% confidence interval for a sample of size 263 with 145 successes. Enter your answer in interval notation using parentheses around the lower and upper bound written as decimals accurate to three decimal places, i.e. (lower bound, upper bound). 99% C.I. =______________

3. Assume that a sample is used to estimate a population proportionp. Find the 95% confidence interval for a sample of size 387 with 170 successes. Enter your answer as an interval using decimals (not percent's) accurate to three decimal places.

(___________ . _________)

4. In a randomly selected sample of 1105 individuals in a state, 751 were in favor of expanding background checks for gun ownership. Construct a 95% confidence interval for the proportion of all individuals in favor of expanding background checks in this state. a)p= _____________

Round to 4 decimal places, if needed.Check requirements:

b). Are the observations independent? Check this by usingn0.05N.

_____________0.05N

What does this tell us the required population size is?Round to 1 decimal place, if needed. N______________

Note, the smallest population of any U.S. state is about 580,000 people.

c) Is the sample size large enough? Check this by usingnp^10andn(1-p^) 10.Round to the nearest whole number.

np=______________

n(1p) =____________

This means that the sampling distribution ofp^is

a). Approximately Normal becausenp^<10andn(1-p^) <10.

b). Not Normal becausenp^<10andn(1-p^) <10.

c). Unknown shape because not enough information is given in the problem.

d). Approximately Normal regardless of sample size.

e). Approximately Normal becausenp^10andn(1-p^) 10.

5. Approximately Normal because the sample sizen30. In a randomly selected sample of 1133 citizens who are registered to vote in the U.S., 516 were satisfied with the job the Supreme Court was doing. Construct a 99% confidence interval for the proportion of all citizens who are registered to vote in the U.S. who are satisfied with the job the Supreme Court was doing. a) p=___________Round to 4 decimal places, if needed.Check requirements:

b) Are the observations independent? Check this by usingn0.05N.

0.05N______________

What does this tell us the required population size is?Round to 1 decimal place, if needed. N__________

c)Is the sample size large enough? Check this by usingnp^10andn(1-p^) 10.Round to the nearest whole number.

np=____________

n(1p) =_____________

This means that the sampling distribution ofp^is

a). Unknown shape because not enough information is given in the problem.

b), Not Normal becausenp^<10andn(1-p^) <10.

c). Approximately Normal because the sample sizen30.

d). Approximately Normal becausenp^<10andn(1-p^) <10.

e). Approximately Normal regardless of sample size.

f). Approximately Normal becausenp^10andn(1-p^) 10.