$$\text{Class Width} = \frac{\text{Max Value} - \text{Min Value}}{\text{Number of Classes}}$$

Question 1

Which of the following best describes a frequency distribution?

Accepted Answer

A table that lists all classes and the number of values in each class, but does NOT maintain the original data values.

Question 2

Given the following class intervals for pulse rates: 60-69, 70-79, 80-89, what is the class width?

Accepted Answer

$$10$$

Question 3

If a frequency distribution has the following classes: 1-10, 11-20, 21-30, what is the lower class limit of the second class?

Accepted Answer

$$11$$

Question 4

How do you calculate the midpoint for the class 80-89?

Accepted Answer

$$\frac{80 + 89}{2} = 84.5$$

Question 5

A class in a frequency distribution has a frequency of 12 and the total number of data values is 40. What is the relative frequency for this class?

Accepted Answer

$$\frac{12}{40} = 0.3$$

Question 6

Which type of graph is most appropriate for displaying the cumulative frequency of a data set?

Accepted Answer

Ogive

Question 7

A histogram is constructed for the pulse rates of females. What does the horizontal axis represent?

Accepted Answer

Classes of pulse rates

Question 8

Which of the following is a key difference between a histogram and a dot plot?

Accepted Answer

A histogram does not maintain original data values, while a dot plot does.

Question 9

Given the following frequencies for pulse rates: 12, 14, 11, 1, 1, 0, 1, what is the cumulative frequency for the class '80-89'?

Accepted Answer

$$12 + 14 + 11 = 37$$

Question 10

Which of the following best describes a frequency polygon?

Accepted Answer

A graph that uses line segments connected to points directly above class midpoints.

Question 11

A company tracks its sales over 20 years and plots the data. Which type of graph is most appropriate?

Accepted Answer

Time series graph

Question 12

Which of the following is a correct formula for calculating class width?

Accepted Answer

$$	ext{Class Width} = \frac{	ext{Max Value} - 	ext{Min Value}}{	ext{Number of Classes}}$$

Question 13

A stemplot is most useful for which of the following?

Accepted Answer

Displaying the distribution of small sets of quantitative data while preserving original values.

Question 14

Which of the following is a potential error in graph construction?

Accepted Answer

Using a histogram for categorical data.

Question 15

A scatter plot is used to:

Accepted Answer

Determine if there is a relationship between two quantitative variables.

Question 16

If a histogram is symmetric, what does this imply about the data distribution?

Accepted Answer

The left and right sides of the histogram are mirror images.

Question 17

Which of the following is NOT a part of a frequency distribution table?

Accepted Answer

Scatter plot

Question 18

In a cumulative frequency distribution, the cumulative frequency for a class is:

Accepted Answer

The sum of the current class frequency and all previous class frequencies.

Question 19

Which of the following best describes class boundaries?

Accepted Answer

Numbers used to separate classes without gaps in a frequency distribution.

Question 20

A relative frequency histogram differs from a regular histogram in that:

Accepted Answer

The vertical axis represents relative frequencies instead of actual frequencies.

Summarizing and Graphing Data (Introductory Statistics Ch. 2)

Study Guide - Practice Questions