1. For each of the variables described below, indicate whether it is a quantitative or a categorical (qualitative) variable. Also, indicate the level of measurement for the variable: nominal, ordinal, interval, or ratio. Make sure your responses are the most specific possible.

Variable

Type of variable Level of measurement

(a)Total elapsed time (in seconds) Quantitative nominal

for completion of an assembly line Categorical ordinal

of operation. interval

ratio

(b)Temperature (in degrees Quantitative Nominal

Fahrenheit) Categorical Ordinal

Interval Ratio

(c)Exchange on which a stock is traded

(NYSE, AMEX, or other) Quantitative Nominal

Categorical Ordinal

Interval

Ratio

2. The following list contains the average annual total returns (in percentage points) for 9 mutual funds. The mutual funds appear in an online brokerage firm's "all-star" list.

39,37,25,-4,34,39,22,39,19

(a) What is the mean of this data set? If your answer is not an integer, round your answer to one decimal place.

(b) What is the median of this data set? If your answer is not an integer, round your answer to one decimal place.

(c) How many modes does the data set have, and what are their values? Indicate the number of modes then indicate the value(s) of the mode(s), if applicable.

zero modes

one mode:

two modes:

3. The following data are the distances from the workplace (in miles) for the 5employees of a small business.

17,13,10,9,1

Assuming that these distances constitute an entire population, find the standard deviation of the population. Round your answer to two decimal places

4. The following are the P/E ratios (price of stock divided by projected earnings per share) for16 banks.

38,17 ,23,22,18,15,43,19,22,34,18,24,22,50,25,23

Find 25th and 60th percentiles for these ratios.

(a) The 25thpercentile: ____ (b) The 60thpercentile ____

5. A nationwide test taken by high school sophomores and juniors has three sections, each scored on a scale of 20to 80 . In a recent year, the national mean score for the writing section was 50.4, with a standard deviation of 9.1. Based on this information, complete the following statements about the distribution of the scores on the writing section for the recent year.

(a)According to Chebyshev's theorem, at least 84 of the scores lie between _ and_.

(Round your answer to 1 decimal place.)

(b)According to Chebyshev's theorem, what %of the scores lie between32.2 and 68.6.

6. Fill in theP(X=x) values to give a legitimate probability distribution for the discrete random variable X, whose possible values are 0 ,1 ,2 ,4 , and 5 .

Value x of X P(X=x)

0 0.12

1 0.29

2 0.11

4 ___

5 ___

7. Anita's, a fast-food chain specializing in hot dogs and garlic fries, keeps track of the proportion of its customers who decide to eat in the restaurant (as opposed to ordering the food "to go") so it can make decisions regarding the possible construction of in-store play areas, the attendance of its mascot Sammy at the franchise locations, and so on. Anita's reports that 52% of its customers order their food to go. Suppose that this proportion is correct and that a random sample of40individual customers is taken.

(a) Estimate the number of customers in the sample who order their food to go by giving the mean of the relevant distribution (that is, the expectation of the relevant random variable). Do not round your response.

(b) Quantify the uncertainty of your estimate by giving the standard deviation of the distribution. Round your response to at least three decimal places.