Question 1

A recent survey by the alumni of a major university indicated that the average salary of 7,500 of its 200,000 graduates was $95,000. Is this value a parameter or a statistic? Why?

Accepted Answer

Statistic, because it describes a sample taken from the population.

Question 2

Which of the following best describes the data set consisting of the colors of automobiles on a used car lot?

Accepted Answer

Qualitative

Question 3

A medical researcher randomly assigns 67 adults with diabetes to a treatment group and 67 to a placebo group. The treatment group receives medication, and the placebo group receives a placebo. At the end of three months, symptoms are evaluated. What type of study is this?

Accepted Answer

Experiment

Question 4

Given the following frequency distribution for heights (in inches):

50-52: 5
53-55: 8
56-58: 12
59-61: 13
62-64: 11

What is the class width, the class midpoint of the first class, and the class boundaries of the first class?

Accepted Answer

(a) 3
(b) 51
(c) $$49.5-52.5$$

Question 5

Refer to the ogive for 'Leisure Time of College Students.' Approximately how many students are in the sample?

Accepted Answer

80

Question 6

Which of the following best describes the shape of the distribution in the histogram for 'Age of patient'?

Accepted Answer

Skewed left

Question 7

The mean length of a human pregnancy is 266 days, with a standard deviation of 9 days. Using the Empirical Rule, what percentage of pregnancies are between 257 and 275 days?

Accepted Answer

68%

Question 8

A student scores 77 on a test where the mean is 81 and the standard deviation is 3. What is the student's z-score?

Use the formula: $$z = \frac{X - \mu}{\sigma}$$

Accepted Answer

$$z = -1.33$$

Question 9

Refer to the box-and-whisker plot for cholesterol levels. Which statement is accurate?

Accepted Answer

One half of the cholesterol levels are between 180 and 211.

Question 10

A single six-sided die is rolled. What is the probability of rolling a seven?

Accepted Answer

0

Question 11

If one card is drawn from a standard deck of 52 playing cards, what is the probability of drawing a heart?

Accepted Answer

$$\frac{1}{4}$$

Question 12

A group of students were asked if they carry a credit card. If 6 out of 40 sophomores carry a credit card, what is the probability that a randomly selected sophomore carries a credit card? (Round to three decimal places.)

Accepted Answer

0.150

Question 13

How many different license plates can be made consisting of 3 letters followed by 2 digits? (Assume repetition is allowed.)

Use the formula: $$26^3$$ 	imes $$10^2$$

Accepted Answer

1,757,600

Question 14

In the Venn diagram, event A represents adults who drink coffee, event B represents adults who drink tea, and event C represents adults who drink cola. Which region(s) represent adults who drink both coffee and tea?

Accepted Answer

Regions 1 and 4

Question 15

Which of the following cannot be a probability?

Accepted Answer

-19

Question 16

A sports team has a three-game road trip. Which outcomes represent the event 'They win exactly two games'?

Accepted Answer

{WWL, WLW, LWW}

Question 17

A study was conducted to determine how people get jobs. The frequencies for job sources are: Online (124), Networking (103), Newspaper (72), Search firm (69), Mailings (32). Which type of chart is most appropriate to display this data?

Accepted Answer

Pareto chart

Question 18

Calculate $$9C3 ($$the number of combinations of 9 items taken 3 at a time).

Use the formula: $$nCr = \frac{n!}{r!(n-r)!}$$

Accepted Answer

84

Statistics Exam Study Guide: Graphs, Data Types, Probability, and Descriptive Measures

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Study guide - Flashcard