Question 1

A data set consists of the following values: 53, 32, 61, 27, 39, 44, 49, 57. What is the mean of this data set? Use the formula $$\bar{x} = \frac{\sum x}{n}.$$

Accepted Answer

$$\bar{x} = 45.25$$

Question 2

Which measure of central tendency is most affected by outliers in a data set?

Accepted Answer

Mean

Question 3

Given the following cash donations (in millions): 319, 199, 110, 63, 21, 315, 26, 63. What is the mean donation? Use $$\bar{x} = \frac{\sum x}{n}.$$

Accepted Answer

$$\bar{x} = 139.5$$

Question 4

A data set has the following values: 10,824, 18,038, 20,352, 40,911, 49,723, 61,848, 173,175. What is the median?

Accepted Answer

40,911

Question 5

Which of the following statements is TRUE regarding the relationship among mean, median, and mode for a distribution skewed to the right?

Accepted Answer

Mode \u003c Median \u003c Mean

Question 6

A company’s 12 highest-paid CEOs have the following compensations (in millions): 21.6, 21.7, 22.9, 25.2, 26.5, 28.0, 28.2, 32.6, 32.9, 70.1, 76.1, 84.5. What is the median compensation?

Accepted Answer

$$28.1$$

Question 7

Which measure of central tendency can be used for both quantitative and qualitative data?

Accepted Answer

Mode

Question 8

A data set has the following values: 23, 36, 12, 23, 47, 32, 8, 12, 26, 31, 18, 28. What is the mode?

Accepted Answer

12 and 23

Question 9

The range of the total areas (in square miles) of Arkansas (53,182), Louisiana (49,651), Oklahoma (69,903), and Texas (267,277) is:

Accepted Answer

217,626

Question 10

Which of the following is a disadvantage of using the range as a measure of dispersion?

Accepted Answer

It is based only on the largest and smallest values

Question 11

Given the following baggage fee revenues (in millions): 313, 342, 581, 952, 514, 152, calculate the sample mean using $$\bar{x} = \frac{\sum x}{n}.$$

Accepted Answer

Question 12

Which formula is used to calculate the sample variance for ungrouped data?

Accepted Answer

$$s^2$$ = \frac{\sum (x - \bar{x}$$)^2$$}{n-1}$$

Question 13

For a bell-shaped distribution, what percentage of data falls within two standard deviations of the mean according to the Empirical Rule?

Accepted Answer

95%

Question 14

Using Chebyshev’s theorem, at least what percentage of values lie within $$k = 3$$ standard deviations of the mean?

Accepted Answer

89%

Question 15

The interquartile range (IQR) is defined as:

Accepted Answer

$$Q_3$$ - $$Q_1$$

Question 16

A data set has $$Q_1 = 30.5$ and Q_3$ = 49. $$What is the interquartile range?

Accepted Answer

18.5

Question 17

Which of the following best describes a box-and-whisker plot?

Accepted Answer

A plot that shows the center, spread, and skewness of a data set

Question 18

If a value is at the 60th percentile in a data set, what does this mean?

Accepted Answer

60% of the values are less than or equal to this value

Question 19

Which of the following is a population parameter?

Accepted Answer

Population variance

Chapter 3: Numerical Descriptive Measures in Statistics

Guida di studio - Domande di pratica

Study guide - Flashcard