1. A POW in solitary confinement tosses a fair coin a large number of times. Assuming the tosses are independent, which of the following is true?

Group of answer choices

Once the number of flips is large enough, the number of heads will always be exactly half of the total number of tosses. For example, after 10,000 tosses I should have exactly 5,000 heads

As the number of tosses increases, any long run of heads will be balanced by a corresponding run of tails so that the overall proportion of heads is exactly 1/2.

The proportion of heads will be about 1/2 and this proportion will tend to get closer to 1/2 as the number of tosses increases.

None of the above

2. A survey of a random sample of 100 nurses working at a large hospital asked how many years they had been working in the profession. Their answers are summarized in the following table.

What proportion of nurses have five or more years of experience?

No of Years	Frequency	Relative Frequency
<5	20	0.20
5-10	30	0.30
>10	50	0.50

0.45

0.75

0.80

0.30

3. How should you classify data from the following question: What is your blood pressure?

Group of answer choices

quantitative - discrete

qualitative

quantitative - continuous

4. According to a study done by Pierce students, the height for Hawaiian adult males is normally distributed with an average of 66 inches and a standard deviation of 2.5 inches. Suppose one Hawaiian adult male is randomly chosen. Let X = height of the individual.

Find the probability that the person is between 63.5 and 68.5 inches.

Group of answer choices

0.7500

0.6800

0.9500

0.8800

5. A Kumai assembly line, which has been operating since 1950, has built an average of 6,000 cars and trucks a week. Generally, 10% of the cars were defective coming off the assembly line. Suppose we draw a random sample of n = 100 cars.

Assume a normal distribution for the defective cars in the sample

n = 100; p = 0.1; q = 0.9

= np = (100)(0.10) = 10

= npq = (100)(0.1)(0.9) = 3

Let X represent the number of defective cars in the sample. What can we say about X in regard to the 68-95-99.7 empirical rule (one standard deviation, two standard deviations and three standard deviations from the mean are being referred to)?

Group of answer choices

68% of the defective cars will fall between seven and 13; 95 % of the defective cars will fall between four and 16; 99.7% of the defective cars will fall between one and 19.

68% of the defective cars will fall between seven and 13; 95 % of the defective cars will fall between four and 16; 99.7% of the defective cars will fall between four and 19.

68% of the defective cars will fall between seven and 13; 95 % of the defective cars will fall between four and 16; 99.7% of the defective cars will fall between one and 22.

68% of the defective cars will fall between seven and 13; 95 % of the defective cars will fall between three and 16; 99.7% of the defective cars will fall between one and 19.

6. Approximately 70% of U.S. adults had at least one pet as a child. We randomly survey 50 U. S. adults. We are interested in the number that had at least one pet as a child. The probability that at least 3 adults had at least one pet as a child means:

Group of answer choices

P(X=3)+P(X=4)+P(X=5)+ ...

P(X=4)+P(X=5)+P(X=6)+ ...

P(X=0)+P(X=1)+P(X=2)

P(X=0)+P(X=1)+P(X=2)+P(X=3)

7. Using the table below, find the expected value.

X	P(X=x)
0	.1
1	.2
2	?
4	.3
6	.3

8. When constructing a confidence interval for the population mean, the case where the population standard deviation is known is __________.

Group of answer choices

possible, and the most common

possible, but not common

not possible

impossible

9. Suppose that the distribution of fly balls hit to the outfield (in baseball) is normally distributed with a mean of 250 feet and a standard deviation of 50 feet. We randomly sample 49 fly balls.

Find the 80th percentile of the distribution of the average of fly balls

Group of answer choices

256.0116 feet

245.2004 feet

233.333 feet

266.2221 feet

10. A study of a certain brand of AA batteries yielded a sample mean lifetime of 450 minutes with a sample standard deviation of 92 minutes. A hypothesis test was performed using the following hypotheses:

Ho : m = 480

Ha : m < 480

The type I error for this hypothesis test is:

Group of answer choices

to conclude that the average battery lifetime is equal to 480 minutes when, in reality, it actually is equal to 480 minutes

to conclude that the average battery lifetime is less than 480 minutes when, in reality, it is equal to 480 minutes

to conclude that the average battery lifetime is equal to 480 minutes when, in reality, it is less than 480 minutes

to conclude that the average battery lifetime is greater than 480 minutes when, in reality, it is equal to 480 minutes

11. A radio news story claimed that half of all U.S. adults have Internet access. In a national poll about Internet usage (The Pew Internet Project), 12,638 U.S. adults were surveyed and it was found that 6413 of those surveyed had Internet access. At a 5% level of significance, perform a hypothesis test to test the claim made by the radio news story.

The correct conclusion is:

Group of answer choices

half of all U.S. adults have Internet access.

less than half of all U.S. adults have Internet access.

The percentage of U.S. adults that have Internet access is not one-half.

more than half of all U.S. adults have Internet access.

12. To assess whether a data set fits a specific distribution, you can apply the ____________hypothesis test that uses the chi-square distribution. The ____hypothesis for this test states that the data come from the assumed distribution. The test compares observed values against the values you would expect to have if your data followed the assumed distribution. The test is almost always _________tailed. Each observation or cell category must have an expected value of at least ______.

Group of answer choices

independence test, alternate, left, ten

goodness-of-fit, null, right, five

homogeneity test, null, right, five

goodness of fit, alternate, left, seven

13. Susan, a personal trainer, was interested in whether or not there was a linear relationship between the number of visits her clients made to the gym each week and the average amount of time her clients exercised per visit. She took the following data.

Client	1	2	3	4	5	6
Number of visits per week	1	3	4	2	3	5
Average time spent exercising per visit (hours)	2	1.5	1	2	2	0.30

If the correlation coefficient is -1, which answer is correct?

Group of answer choices

The slope of the best fit line is positive.

The data fit exactly on a line with negative slope.

The slope of the best fit line is -1.

The data fit exactly on a line with positive slope.

14. The correlation coefficient, r, developed by Karl Pearson in the early 1900s, is numerical and provides a measure of strength and direction of the linear association between the independent variable x and the dependent variable y.

Group of answer choices

True

False

15. The chi-square distribution curve is skewed to the ______, and its shape depends on the degrees of freedom df. For df > ____, the curve approximates the ________ distribution. Test statistics based on the chi-square distribution are always greater than or equal to _____. Such application tests are almost always right-tailed tests.

Group of answer choices

right, 90, normal, zero

left, 15, exponential, 50

right, 2, uniform, 50

left, 90, normal, 1