Question 1

Which of the following graphical methods is most appropriate for displaying the distribution of a single quantitative variable?

Accepted Answer

Histogram

Question 2

A company wants to show the breakdown of its sales by region as a percentage of total sales. Which visual presentation should they use?

Accepted Answer

Pie chart

Question 3

Given the data set: 10, 15, 20, 25, 30, what is the mean?

Accepted Answer

$$\frac{10+15+20+25+30}{5} = 20$$

Question 4

Which measure of central tendency is least affected by extreme values in a data set?

Accepted Answer

Median

Question 5

A sample of five stock prices is: 5, 1, 3, 2, 3. What is the sample variance? Use the formula $$s^2$$ = \frac{\sum (x_i - \bar{x}$$)^2$$}{n-1}$$.

Accepted Answer

$$s^2 = 2.5$

Question 6

Which of the following is NOT a measure of dispersion?

Accepted Answer

Median

Question 7

If a data set is symmetric, which statement is most likely true?

Accepted Answer

The mean and median are equal.

Question 8

A Pareto diagram is different from a bar graph because:

Accepted Answer

It arranges categories in descending order of frequency.

Question 9

What is the formula for the sample standard deviation?

Accepted Answer

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

Question 10

Which of the following best describes a stem-and-leaf display?

Accepted Answer

It divides each observation into a stem and a leaf, displaying them in columns.

Question 11

A class has 8 freshmen, 13 sophomores, 5 juniors, and 3 seniors. What is the relative frequency of juniors?

Accepted Answer

$$\frac{5}{29} \approx 0.17$$

Question 12

Which of the following is a qualitative variable?

Accepted Answer

Class standing (Freshman, Sophomore, etc.)

Question 13

If the ordered data set is: 4.5, 6.3, 7.7, 8.9, 10.1, 11.5, what is the median?

Accepted Answer

$$\frac{7.7 + 8.9}{2} = 8.3$$

Question 14

Which statement about the mode is correct?

Accepted Answer

It is not affected by extreme values.

Question 15

A dot plot is most useful for:

Accepted Answer

Displaying the distribution of a small quantitative data set.

Question 16

Which formula is an alternative way to compute sample variance?

Accepted Answer

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

Question 17

Which of the following is NOT a characteristic of the median?

Accepted Answer

It is affected by extreme values.

Question 18

In a frequency histogram, what does the height of each bar represent?

Accepted Answer

The frequency of observations in each class interval

Question 19

Which of the following best describes the range?

Accepted Answer

The difference between the largest and smallest observations

Question 20

If a distribution is skewed to the right, which of the following is most likely true?

Accepted Answer

The mean is greater than the median.

Visual Presentation and Numerical Measures: Describing Data in Business Statistics

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