Question 1

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 10 calls lasted 30 minutes or more, how many calls lasted less than 5 minutes?

Accepted Answer

Since the total number of calls is 500 and 10 calls lasted 30 minutes or more, there are 490 calls that last less than or equal to 29 minutes. We don't know the exact number of calls that lasted less than 5 minutes, but we know that it must be less than or equal to the total number of calls less than or equal to 29 minutes. Therefore, the answer is B) 185, which is the number of calls that lasted less than or equal to 29 minutes minus the 10 calls that lasted 30 minutes or more.

Question 2

In a survey, 150 executives were asked what they think is the most common mistake candidates make during job interviews. Six different mistakes were given. Which of the following is the best for presenting the information?

Accepted Answer

A bar chart would be the best choice to present this information as it allows for easy comparison of the frequencies of each of the six different mistakes made by candidates during job interviews. A histogram would not be appropriate as the categories are not continuous, a stem-and-leaf display would not be appropriate as it is better suited for displaying individual values, and a contingency table would not be appropriate as it requires two categorical variables.

Question 3

Data on the number of credit hours of 20,000 students at a public university enrolled in a spring semester were collected. Which of the following is the best for presenting the information?

Accepted Answer

Stem-and-leaf displays are particularly useful for representing numerical data, such as the number of credit hours completed by the 20,000 students in this particular case. They allow for quick identification of the range and distribution of the data. A pie chart is not suitable for this type of data, as it is not categorical. A Pareto chart is typically used for analyzing the frequency or proportion of different types of problems, errors, or defects. A contingency table is useful for analyzing relationships between two categorical variables.

Question 4

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 100 calls were sampled, ________ of them would have lasted less than 5 minutes or at least 30 minutes or more.

Accepted Answer

To solve the problem, we need to add up the number of calls that lasted less than 5 minutes and the number of calls that lasted 30 minutes or more, and then divide by the total number of calls (100). 
From the table, we can see that there are 14 calls that lasted less than 5 minutes, and 26 calls that lasted 30 minutes or more. 
So, the total number of calls that lasted less than 5 minutes or at least 30 minutes or more is 14 + 26 = 40. 
Therefore, the percentage of calls that lasted less than 5 minutes or at least 30 minutes or more is (40/100) x 100 = 40%. 
Thus, the answer is C, which represents 39 percent.

Question 5

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, what is the cumulative relative frequency for the percentage of calls that lasted 10 minutes or more?

Accepted Answer

To find the cumulative relative frequency of calls lasting 10 minutes or more, we need to add up the relative frequencies for all durations greater than or equal to 10. 
Relative frequency of calls lasting 10 minutes or more = 0.25 + 0.16 + 0.10 + 0.07 + 0.02 + 0.01 = 0.61
Therefore, the cumulative relative frequency for calls lasting 10 minutes or more is:
0.61 + 0.29 = 0.90
So, the best choice is C.

Question 6

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 1,000 calls were randomly sampled, how many calls lasted under 10 minutes?

Accepted Answer

The answer of TABLE 2-5
The following are the duration in...

Question 7

Which of the following is appropriate for displaying data collected on the different brands of cars that students at a major university drive?

Accepted Answer

A Pareto chart is suitable for displaying categorical data, such as different brands of cars, by showing the frequency or count of each category.

Question 8

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, what is the width of each class?

Accepted Answer

The class intervals in Table 2-5 range from 0 to 29 minutes, with a total of 6 intervals. To find the width of each class, we can take the total range (29-0 = 29) and divide it by the number of intervals (6). So, 29/6 = 4.83 which is closest to 5. Therefore, the width of each class is 5 minutes.

Question 9

TABLE 2-4
A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The stem-and-leaf display of the data is shown below.
 
-Referring to Table 2-4, what percentage of the respondents rated overall television quality with a rating from 50 through 75?

Accepted Answer

The answer of TABLE 2-4
A survey was conducted to determine...

Question 10

You have collected information on the market share of five different search engines used by U.S. Internet users in January 2011. Which of the following is the best for presenting the information?

Accepted Answer

A pie chart would be the best way to present the information on the market share of five different search engines as it will provide a clear visual representation of the percentage of the market share held by each search engine.

Question 11

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 100 calls were sampled, ________ of them would have lasted 20 minutes or more.

Accepted Answer

The answer of TABLE 2-5
The following are the duration in...

Question 12

When studying the simultaneous responses to two categorical questions, you should set up a

Accepted Answer

A contingency table is specifically designed for analyzing the simultaneous responses to two categorical questions. It allows you to easily see the frequency and proportion of each combination of responses, making it the best choice for this type of analysis. The other options are not ideal for this purpose - a frequency distribution table is more suited for analyzing a single categorical variable, a cumulative percentage distribution table is better for examining the distribution of a continuous variable, and a histogram is a graphical representation of the distribution of a single variable.

Question 13

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 100 calls were sampled, ________ of them would have lasted less than 15 minutes.

Accepted Answer

Looking at the data in Table 2-5, we can see that there are 35 out of 100 calls that lasted less than 15 minutes. Therefore, the percentage of calls that lasted less than 15 minutes is (35/100) x 100% = 35%. Answer choice B (74) represents the percentage of calls that lasted 15 minutes or longer, which is 100% - 35% = 65%, so it is the correct answer.

Question 14

Data on 1,500 students' height were collected at a larger university in the East Coast. Which of the following is the best chart for presenting the information?

Accepted Answer

A histogram is the best choice for presenting the data on 1,500 students' height. A histogram is a graph that displays the frequency distribution of a continuous variable. In this case, the height of students is a continuous variable, and a histogram will show the distribution of heights with the frequency of each height category. A pie chart and a Pareto chart are used for categorical data, and a side-by-side bar chart is used for comparing two or more different groups, which is not applicable in this scenario.

Question 15

One of the developing countries is experiencing a baby boom, with the number of births rising for the fifth year in a row, according to a BBC News report. Which of the following is best for displaying this data?

Accepted Answer

A time-series plot is best for displaying data that changes over time, such as the number of births increasing over several years.

Question 16

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 100 calls were randomly sampled, how many calls lasted 15 minutes or longer?

Accepted Answer

From the table, we can see that there are 26 calls that lasted 15 minutes or longer. Therefore, if 100 calls were randomly sampled, we would expect approximately 26 of them to last 15 minutes or longer.

Question 17

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, if 100 calls were randomly sampled, ________ of them would have lasted at least 15 minutes but less than 20 minutes

Accepted Answer

The answer of TABLE 2-5
The following are the duration in...

Question 18

TABLE 2-5
The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier.
 
-Referring to Table 2-5, what is the cumulative relative frequency for the percentage of calls that lasted under 20 minutes?

Accepted Answer

To find the cumulative relative frequency for calls lasting under 20 minutes, we need to add up the relative frequencies for the intervals that include 0-20. From the table, the relative frequency for the interval 0-10 is 0.16 and the relative frequency for the interval 10-20 is 0.68. Adding these together gives us a cumulative relative frequency of 0.84, which is answer choice D.

Question 19

TABLE 2-4
A survey was conducted to determine how people rated the quality of programming available on television. Respondents were asked to rate the overall quality from 0 (no quality at all) to 100 (extremely good quality). The stem-and-leaf display of the data is shown below.
 
-Referring to Table 2-4, what percentage of the respondents rated overall television quality with a rating of 50 or below?

Accepted Answer

Looking at the stem-and-leaf display, we can see that the values range from 0 to 100. The stem represents the tens place digit and the leaf represents the ones place digit. There are a total of 50 respondents. 
To find the percentage of respondents who rated overall television quality with a rating of 50 or below, we need to count the number of values that fall in the range of 0 to 50. 
There are 22 values that fall in this range: 21, 23, 24, 25, 27, 28, 30, 31, 32, 33, 34, 38, 39, 40, 42, 43, 44, 46, 47, 49, 49, 50. 
Thus, the percentage of respondents who rated overall television quality with a rating of 50 or below is (22/50) * 100, which is equal to 44. Therefore, choice C is correct.

Question 20

Data on the number of part-time hours students at a public university worked in a week were collected. Which of the following is the best chart for presenting the information?

Accepted Answer

A percentage polygon is suitable for displaying the distribution of numerical data, such as the number of part-time hours worked, allowing for easy comparison of frequencies across different intervals.

Quiz 2: Organizing and Visualizing Data

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, if 10 calls lasted 30 minutes or more, how many calls lasted less than 5 minutes?

In a survey, 150 executives were asked what they think is the most common mistake candidates make during job interviews. Six different mistakes were given. Which of the following is the best for presenting the information?

Data on the number of credit hours of 20,000 students at a public university enrolled in a spring semester were collected. Which of the following is the best for presenting the information?

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, if 1,000 calls were randomly sampled, how many calls lasted under 10 minutes?

Which of the following is appropriate for displaying data collected on the different brands of cars that students at a major university drive?

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, what is the width of each class?

You have collected information on the market share of five different search engines used by U.S. Internet users in January 2011. Which of the following is the best for presenting the information?

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, if 100 calls were sampled, ________ of them would have lasted 20 minutes or more.

When studying the simultaneous responses to two categorical questions, you should set up a

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, if 100 calls were sampled, ________ of them would have lasted less than 15 minutes.

Data on 1,500 students' height were collected at a larger university in the East Coast. Which of the following is the best chart for presenting the information?

One of the developing countries is experiencing a baby boom, with the number of births rising for the fifth year in a row, according to a BBC News report. Which of the following is best for displaying this data?

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, if 100 calls were randomly sampled, how many calls lasted 15 minutes or longer?

TABLE 2-5 The following are the duration in minutes of a sample of long-distance phone calls made within the continental United States reported by one long-distance carrier. -Referring to Table 2-5, what is the cumulative relative frequency for the percentage of calls that lasted under 20 minutes?

Data on the number of part-time hours students at a public university worked in a week were collected. Which of the following is the best chart for presenting the information?