Name:    07-08 Population Proportions

Multiple Choice
Identify the choice that best completes the statement or answers the question.

1.

 A customer bought a large bag  of several fun size (mini) bags of Skittles.  She decided to open up one of the bags to see how many purple skittles were in a single fun size bag.  She noticed that there were 6 purple out of 24 total in the bag.  Determine ,  the approximate point estimate of the population proportion of purple skittles.
 a. c. b. d.

2.

 A teacher was conducting a study to about the population proportion of students that wear glasses in his school by investigating samples. In his classroom 15 out of his 28 students wear glasses.Based on the samples of size 28, determine ,  the approximate standard deviation of the sampling distribution.
 a. d. b. e. c. f.

3.

Which statement is always exactly true?

 a. b. c.

4.

At a department store, there are a total of 62 total employees. 28 of whose employees work at the store full time.  The store manager realizes that she has a sample of 8 cashiers working one night and only 2 of the cashiers were full-time.  If the store manager was conducting a study of the proportion of full-time employees, are the requirements of  and met to guarantee the sampling distribution is relatively normally distributed?

 a. No.  Both conditions are NOT met. b. No.  Only the condition is NOT met. c. No.  Only the condition is NOT met. d. Yes. Both conditions are met.

5.

 A researcher wishes to conduct a new study on the proportion of the population of U.S. high school graduates that will immediately enlist in the military. Last years study suggested it was roughly 2%.  What is the minimum sample size the researcher should use to ensure the distribution of the sample proportions are relatively normal?  (There are approximately 3.2 million U.S. high school graduates each year.)
 a. The minimum sample size would be 11. b. The minimum sample size would be 320. c. The minimum sample size would be 511. d. The minimum sample size would be 160,000.

6.

Given   and  , construct a 99% confidence interval for a range estimate of  p.

(Critical value for 99% confidence, )

 a. c. b. d.

7.

 In the last few decades, more females attend college than do males in the U.S.  A researcher conducted a simple random sample of 300 college students in the U.S. and 186 were female.Construct a 95% confidence interval for the proportion of U.S. college students that are female. (Critical value for 95% confidence, )
 a. c. b. d.

8.

 A political researcher wanted to know if the candidate, Jack Johnson, who he is working for would win the election. So, he conducted a random sample of 150 constituents in a voting district of 1,902,000.  He found that 90 of the 150 said they were definitely voting for Jack Johnson.Can you say using a 99% confidence interval that Jack Johnson will receive at least 52% of the vote? (Critical value for 99% confidence, )
 a. No, the 99% CI suggests Jack Johnson will receive at least 47.3%  of the vote. b. No, the 99% CI suggests Jack Johnson will receive at least 49.7%  of the vote. c. Yes, the 99% CI suggests Jack Johnson will receive at least 53.2%  of the vote. d. Yes, the 99% CI suggests Jack Johnson will receive at least 56% of the vote.

9.

A 99% confidence interval was conducted for p to be:

What was the point estimate   used to construct the interval?

(Critical value for 99% confidence, )

 a. c. b. d.

10.

A 99% confidence interval was conducted for p to be:

What was most likely sample size, n, used?

(Critical value for 99% confidence, )

 a. c. b. d.