Deck 2: Descriptive Statistics

Question 1

_______________ act(s) as a representative of the population.

A)The analytics
B)The variance
C)A sample
D)The random variables

Answer 1

A sample

Question 2

The data collected from the customers in restaurants about the quality of food is an example of a(n)

A)variable study.
B)cross-sectional study.
C)experimental study.
D)observational study.

Answer 2

observational study.

Question 3

A set of values corresponding to a set of variables is defined as a(n)

A)quantity.
B)event.
C)factor.
D)observation.

Answer 3

observation.

Question 4

In a(n) ________________, one or more variables are identified and controlled or manipulated so that data can be obtained about how they influence the variable of interest identified first.

A)experimental study
B)observational study
C)categorical study
D)variable study

Question 5

Data collected from several entities over a period of time (minutes, hours, days, etc.) are called

A)categorical and quantitative data.
B)time series data.
C)source data.
D)cross-sectional data.

Question 6

A _______________ is a graphical summary of data previously summarized in a frequency distribution.

A)box plot
B)histogram
C)line chart
D)scatter chart

Question 7

____________________ are collected from several entities at the same point in time.

A)Time series data
B)Categorical and quantitative data
C)Cross-sectional data
D)Random data

Question 8

Which of the following are necessary to be determined to define the classes for a frequency distribution with quantitative data?

A)Number of nonoverlapping bins, width of each bin, and bin limits
B)Width of each bin and bin lower limits
C)Number of overlapping bins, width of each bin, and bin upper limits
D)Width of each bin and number of bins

Question 9

Consider the data below. What percentage of students scored grade C? $$\begin{array} { c | c } \text { Grades } & \begin{array} { c } \text { Number of } \\\text { students }\end{array} \\\hline \text { A } & 16 \\\text { B } & 28 \\\text { C } & 33 \\\text { D } & 13 \\\hline \text { Total } & 90\end{array}$$

A)33%
B)31%
C)37%
D)28%

Question 10

The letter grades of business analysis students is recorded by a professor (4=A, 3=B, 2=C, 1=D). This variable's classification

A)is quantitative data.
B)cannot be determined.
C)is categorical data.
D)is nominal data.

Question 11

A quantity of interest that can take on different values is known as a(n)

A)variable.
B)parameter.
C)sample.
D)observation.

Question 12

The data on the time taken by 10 students in a class to complete an exam is an example of what type of data?

A)Cannot be determined
B)Categorical data
C)Time series data
D)Quantitative data

Question 13

Compute the relative frequencies for the data given in the table below: $$\begin{array} { c | c } \text { Grades } & \begin{array} { c } \text { Number of } \\\text { students }\end{array} \\\hline \text { A } & 16 \\\text { B } & 28 \\\text { C } & 33 \\\text { D } & 13 \\\hline \text { Total } & 90\end{array}$$

A)0.31, 0.14, 0.37, 0.18
B)0.37, 0.14, 0.31, 0.18
C)0.16, 0.28, 0.33, 0.13
D)0.18, 0.31, 0.37, 0.14

Question 14

The goal regarding using an appropriate number of bins is to show the

A)number of observations.
B)number of variables.
C)variation in the data.
D)correlation in the data.

Question 15

Which of the following gives the proportion of items in each bin?

A)Frequency
B)Class size
C)Relative frequency
D)Bin proportion

Question 16

When working with large spreadsheets with many rows of data, it can be helpful to ____________ the data to better find, view, or manage subsets of data.

A)split
B)sort and filter
C)chart
D)manipulate

Question 17

The difference in a variable measured over observations (time, customers, items, etc.) is known as

A)observed differences.
B)variation.
C)variable change.
D)descriptive analytics.

Question 18

A summary of data that shows the number of observations in each of several nonoverlapping bins is called a(n)

A)frequency distribution.
B)sample summary.
C)bin distribution.
D)observed distribution.

Question 19

The act of collecting data that are representative of the population data is called

A)random sampling.
B)sample data.
C)population sampling.
D)applications of business analytics.

Question 20

Identify the shape of the distribution in the figure below.

A)Moderately skewed left
B)Symmetric
C)Approximately Bell Shaped
D)Moderately skewed right

Question 21

The ______________________ shows the number of data items with values less than or equal to the upper class limit of each class.

A)cumulative frequency distribution
B)frequency distribution
C)percent frequency distribution
D)relative frequency distribution

Question 22

Compute the third quartile for the following data. 10, 15, 17, 21, 25, 12, 16, 11, 13, 22

A)21.25
B)15.5
C)21.5
D)11.75

Question 23

Use technology to compute the standard deviation for the following sample data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37

A)5.96
B)6.41
C)5.42
D)6.75

Question 24

For data having a bell-shaped distribution, approximately _____ percent of the data values will be within one standard deviation of the mean.

A)95
B)66
C)68
D)97

Question 25

Compute the IQR for the following data. 10, 15, 17, 21, 25, 12, 16, 11, 13, 22

A)6.25
B)7.75
C)5.14
D)9.50

Question 26

The simplest measure of variability is the

A)variance.
B)standard deviation.
C)coefficient of variation.
D)range.

Question 27

A _____________________ determines how far a particular value is from the mean relative to the data set's standard deviation.

A)coefficient of variation
B)z-score
C)variance
D)percentile

Question 28

The ________________ is a point estimate of the population mean for the variable of interest.

A)sample mean
B)median
C)sample
D)geometric mean

Question 29

Compute the coefficient of variation for the following sample data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37

A)18.64%
B)21.36%
C)20.28%
D)21.67%

Question 30

The variance is based on the

A)deviation about the median.
B)number of variables.
C)deviation about the mean.
D)correlation in the data.

Question 31

Compute the mode for the following data. 12, 16, 19, 10, 12, 11, 21, 12, 21, 10

A)21
B)11
C)12
D)10

Question 32

Scores on Ms. Bond's test have a mean of 70 and a standard deviation of 11. Michelle has a score of 48. Convert Michelle's score to a z-score. (Round to two decimal places if necessary.)​

A)​2
B)​41.64
C)-2
D)​1.33

Question 33

The correlation coefficient will always take values

A)greater than 0.
B)between -1 and 0.
C)between -1 and +1.
D)less than -1.

Question 34

Any data value with a z-score less than -3 or greater than +3 is considered to be a(n)

A)outlier.
B)usual value.
C)whisker.
D)z-score value.

Question 35

Compute the geometric mean for the following data on growth factors of an investment for 10 years. 1.10, 0.50, 0.70, 1.21, 1.25, 1.12, 1.16, 1.11, 1.13, 1.22

A)1.0221
B)1.0148
C)1.0363
D)1.1475

Question 36

Compute the 50^th percentile for the following data. 10, 15, 17, 21, 25, 12, 16, 11, 13, 22

A)18.6
B)13.3
C)15.5
D)17.7

Question 37

If covariance between two variables is near 0, it implies that

A)a positive relationship exists between the variables.
B)the variables are not linearly related.
C)the variables are negatively related.
D)the variables are strongly related.

Question 38

Which of the following graphs provides information on outliers and IQR of a data set?

A)Histogram
B)Line chart
C)Scatter chart
D)Box plot

Question 39

Compute the median of the following data. 32, 41, 36, 24, 29, 30, 40, 22, 25, 37

A)28
B)31
C)40
D)34

Question 40

Compute the mean of the following data. 56, 42, 37, 29, 45, 51, 30, 25, 34, 57

A)42.8
B)52.1
C)40.6
D)39.4

Question 41

The College Board reported that, in 2014, the mean Math Level 2 SAT subject test score was 686 with a standard deviation of 96. Assuming scores follow a bell-shaped distribution, use the empirical rule to find the percentage of students who scored less than 494.

A)97.5%
B)95%
C)​2.5%
D)​5%

Question 42

A survey on the most preferred newspaper in the USA listed The New York Times(TNYT), Washington Post(WP), Daily News(DN), New York Post(NYP), and Los Angeles Times (LAT) as the top five most preferred newspapers. The table below shows the preferences of 50 citizens.
a. Are these data categorical or quantitative?
b. Provide frequency and percent frequency distributions.
c. On the basis of the sample, which newspaper is preferred the most?

Question 43

Scores on Ms. Bond's test have a mean of 70 and a standard deviation of 11. David has a score of 52 on Ms. Bond's test. Scores on Ms. Nash's test have a mean of 64 and a standard deviation of 6. Steven has a score of 52 on Ms. Nash's test. Which student has the higher standardized score?

A)David's standardized score is -1.64 and Steven's standardized scores -2.00. Therefore, David has the higher standardized score.
B)David's standardized score is -1.64 and Steven's standardized scores -2.00. Therefore, Steven has the higher standardized score.
C)​David's standardized score is 1.64 and Steven's standardized scores 2.00. Therefore, Steven has the higher standardized score.
D)​Cannot be determined with the information provided.

Question 44

Suppose that you make a fixed deposit of $1,000 in Bank X and $500 in Bank Y. The value of each investment at the end of each subsequent year is provided in the table.
​ ​
Which of the two banks provides a better return over this time period?

Question 45

Suppose that the average time an employee takes to reach the office is 35 minutes. To address the issue of late comers, the mode of transport chosen by the employee is tracked: private transport (two-wheelers and four-wheelers) and public transport. The data on the average time (in minutes) taken using both a private transportation system and a public transportation system for a sample of employees are given below.
a. Considering the travel times (in minutes) of employees using private transport, compute the z-score for the tenth employee with travel time of 29 minutes.
b. Considering the travel times (in minutes) of employees using public transport, compute the z-score for the second employee with travel time of 29 minutes. How does this z-score compare with the z-score you calculated for part a?
c. Based on z-scores, do the data for employees using private transport and public transport contain any outliers?

Question 46

Consider the following data on income and savings of a sample of residents in a locality:
a. Compute the correlation coefficient. Is there a positive correlation between the income and savings? What is your interpretation?
b. Show a scatter diagram of the relationship between the income and savings.

Question 47

Suppose that the average time an employee takes to reach the office is 35 minutes. To address the issue of late comers, the mode of transport chosen by the employee is tracked: private transport (two-wheelers and four-wheelers) and public transport. The data on the average time (in minutes) taken using both a private transportation system and a public transportation system for a sample of employees are given below.
a. What are the mean and median travel times for employees using a private transport? What are the mean and median travel times for employees using a public transport?
b. What are the variance and standard deviation of travel times for employees using a private transport? What are the variance and standard deviation of travel times for employees using a public transport?
c. Comment on the results.

Question 48

A study on the average minutes spent by students on internet usage is 300 with a standard deviation of 102. Answer the following questions assuming a bell-shaped distribution and using the empirical rule.
a. What percentage of students use internet for more than 402 minutes?
b. What percentage of students use internet for more than 504 minutes?
c. What percentage of students use internet between 198 minutes and 300 minutes?

Question 49

The College Board originally scaled SAT scores so that the scores for each section were approximately normally distributed with a mean of 500 and a standard deviation of 100. Assuming scores follow a bell-shaped distribution, use the empirical rule to find the percentage of students who scored less than 400.

A)​16%
B)​68%
C)​84%
D)32%

Question 50

The partial relative frequency distribution is given below:
a. What is the relative frequency of group 4?
b. The total sample size is 400. What is the frequency of group 4?
c. Show the frequency distribution.
d. Show the percent frequency distribution.

Question 51

A student willing to participate in a debate competition is required to fill out a registration form. State whether each of the following information about the participant provides categorical or quantitative data.
a. What is your date of birth?
b. Have you participated in any debate competition previously?
c. If yes, in how many debate competitions have you participated so far?
d. Have you won any of the competitions?
e. If yes, how many have you won?

Question 52

The average time a customer service executive takes to resolve an issue on a mobile handset is 26.4 minutes. The average times taken to resolve the issue by a sample of 15 such executives are shown below.
a. What is the mean resolution time?
b. What is the median resolution time?
c. What is the mode for these 15 executives?
d. What is the variance and standard deviation?
e. What is the third quartile?

Question 53

The results of a survey showed that, on average, children spend 5.6 hours at PlayStation per week. Suppose that the standard deviation is 1.7 hours and that the number of hours at PlayStation follows a bell-shaped distribution.
a. Use the empirical rule to calculate the percentage of children who spend between 2.2 and 9 hours at PlayStation per week.
b. What is the z-value for a child who spends 7.5 hours at PlayStation per week?
c. What is the z-value for a child who spends 4.5 hours at PlayStation per week?

Question 54

Scores on Ms. Nash's test have a mean of 64 and a standard deviation of 9. Steve has a score of 52. Convert Steve's score to a z-score. (Round to two decimal places if necessary.)

A)​1.33
B)​58.2
C)-2
D)-​1.33

Question 55

The College Board originally scaled SAT scores so that the scores for each section were approximately normally distributed with a mean of 500 and a standard deviation of 100. Assuming scores follow a bell-shaped distribution, use the empirical rule to find the percentage of students who scored greater than 700.

A)97.5%
B)95%
C)​2.5%
D)​5%

Question 56

Consider a sample on the waiting times (in minutes) at the billing counter in a grocery store to be 15, 24, 18, 15, 21, 20, 15, 22, 19, 16, 15, 22, 20, 15, and 21. Compute the mean, median, and mode.

Question 57

Eight observations taken for two variables are as follows:
a. Develop a scatter diagram with x on the horizontal axis.
b. What does the scatter diagram developed in part (a) indicate about the relationship between the two variables?
c. Compute and interpret the sample covariance.
d. Compute and interpret the sample correlation coefficient.

Question 58

Consider a sample on the waiting times (in minutes) at the billing counter in a grocery store to be 15, 24, 18, 15, 21, 20, 15, 22, 19, 16, 15, 22, 20, 15, and 21. Compute the 25^th, 50^th, and 75^th percentiles.

Question 59

The mentor of a class researched the number of hours spent on study in a week by each student of the class in order to analyze the correlation between the study hours and the marks obtained by each student. The data on the hours spent per week by 25 students are listed below.
a. What is the least amount of time a student spent per week on studying in this sample? The highest?
b. Use a class width of 2 hours to prepare a frequency distribution, a relative frequency distribution, and a percent frequency distribution for the data.
c. Prepare a histogram and comment on the shape of the distribution.

Question 60

The following table provides information on the number of billionaires in a country and the continents on which these countries are located.
a. Sort the countries from largest to smallest based on the number of billionaires. What are the top five countries according to the number of billionaires?
b. Filter the countries to display only the countries located in North America.

Question 61

What is the relative frequency for Devon Pride? ? $$\begin{array}{l}2015 \text { Contest Sales }\\\begin{array} { l | c | c } \hline \text { Salesman } & \text { Frequency } & \text { Relative Frequency } \\\hline \text { Frances Clonts } & 15 & 0.05 \\\text { Sarah Leigh } & 184 & 0.62 \\\text { Devon Pride } & 37 & \\\text { John Townes } & 62 & 0.21 \\\hline \text { Total } & 298 &\end{array}\end{array}$$ ?

A)0.12
B)99.12
C)0.88
D)Not enough information

Question 62

Compute the relative frequencies for students who earned an A shown in the table of grades below. ? $$\begin{array} { l | c } \text { Grades } & \text { Number of Students } \\\hline \text { A } & 10 \\B & 31 \\C & 36 \\D & 6 \\\hline & \mathbf { 8 3 }\end{array}$$ ?

A)0.12
B)0.10
C)?0.83
D)Not enough information

Question 63

You have been asked to reorganize the Excel table below into order of sales using the Sales column. Which option will allow you to do this quickly? ? $\begin{array}{llllrlclr}\text { Customer ID }&\text {First}&\text { Last }&\text {Sales }&\text {Quantity}&\text { Discount }&\text {Profit }\\\text { CG-12520 } & \text { Claire } & \text { Gute } & \$ 261.96 & 2 & 0 & \$ 41.91 \\\text { DV-13045 } & \text { Darrin } & \text { VanHuff } & \$ 14.62 & 2 & 0 & \$ 16.87 \\\text { SO-20335 } & \text { Sean } & \text { O'Donnell } & \$ 9557.58 & 5 & 0.45 & \$ (383.03) \\\text { BH-11710 } & \text { Brosina } & \text { Hoffman } & \$ 48.86 & 7 & 0 & \$ 14.17 \\\text { AA-10480 } & \text { Andrew } & \text { Allen } & \$ 25.55 & 3 & 0.2 & \$ 5.44 \\\text { IM-15070 } & \text { Irene } & \text { Maddox } & \$ 407.98 & 3 & 0.2 & \$ 132.59 \\\text { HP-14815 } & \text { Harold } & \text { Pawlan } & \$ 68.81 & 5 & 0.8 & \$(123.86) \\\text { PK-19075 } & \text { Pete } & \text { Kriz } & \$ 665.88 & 6 & 0 & \$ 13.32 \\\text { AG-10270 } & \text { Alejandro Grove } & \$ 55.50 & 2 & 0 & \$ 9.99 \\\text { ZD-21925 } & \text { Zuschuss } & \text { Donatelli } & \$ 8.56 & 2 & 0 & \$ 2.48\end{array}$ ?
?

A)?Use the Cut and Paste function to reorganize the data into order of sales.
B)?Use the Filter function to organize the data into order of sales.
C)?Use the Order function to organize the data into order of sales.
D)?Use the Sort function to organize the data into order of sales.

Question 64

Which Excel command will return all modes when more than one mode exists? ​​

A)MODE.MULT
B)​MODE.SNGL
C)MODE
D)MODES

Question 65

Which graph represents a negative linear relationship between x and y? ​ ​
​

A)​A
B)​B
C)​C
D)​None of the graphs display a negative linear relationship.

Question 66

What is the total relative frequency? ? $$\begin{array}{l}2015 \text { Contest Sales }\\\begin{array} { l | c | c } \hline \text { Salesman } & \text { Frequency } & \text { Relative Frequency } \\\hline \text { Frances Clonts } & 15 & 0.05 \\\text { Sarah Leigh } & 184 & 0.62 \\\text { Devon Pride } & 37 & \\\text { John Townes } & 62 & 0.21 \\\hline \text { Total } & 298 &\end{array}\end{array}$$ ?

A)1
B)99.12
C)0.88
D)Not enough information

Question 67

Compute the relative frequencies for students who earned a C shown in the table of grades below. ? $$\begin{array} { l | c } \text { Grades } & \text { Number of Students } \\\hline \text { A } & 10 \\B & 31 \\C & 36 \\D & 6 \\\hline & \mathbf { 8 3 }\end{array}$$ ?

A)0.43
B)0.53
C)?0.83
D)Not enough information

Question 68

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the relative frequency of the 21-24 bin? ​ ​

A)0.05
B)0.14
C)​0.25
D)2.5

Question 69

A sample of 13 adult males' heights are listed below. ​
70, 72, 71, 70, 69, 73, 69, 68, 70, 71, 67, 71, 74
​
Find the range of the data.
​

A)7
B)​6.5
C)​5
D)​4

Question 70

What is the mode of the data set given below? ​
35, 47, 65, 47, 22
​​ ​

A)47.5
B)47
C)65
D)22

Question 71

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the frequency of the 25-28 bin? ​ ​

A)0.05
B)1
C)​0.5
D)4

Question 72

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the relative frequency of the 21-24 bin?
​ ​

Question 73

Select the histogram that is moderately skewed right. ​ ​ ​

A)A
B)B
C)C
D)D

Question 74

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the relative frequency of the 25-28 bin?
​ ​

Question 75

In a survey of patients in a local hospital, 62.42% of the respondents indicated that the health care providers needed to spend more time with each patient. What is the population being studied? ​​

A)​All patients in a local hospital
B)​All survey respondents
C)​Hospital patients
D)​Cannot be determined from the information given

Question 76

Below is the data for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. ​
56, 42, 37, 29, 45, 51, 30, 25, 34, 57
​
What is the median number of days that it took Wyche Accounting to perform audits in the last quarter of last year?
​

A)​41
B)​40.6
C)​39.5
D)​42

Question 77

Below is a histogram for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year. What is the bin size for the histogram? ​ ​

A)3
B)4
C)16
D)5

Question 78

James's manager asked him to sort the last names in the following list in descending order. What does this mean? ? $\begin{array}{llllrlclr}\text { Customer ID }&\text {First}&\text { Last }&\text {Sales }&\text {Quantity}&\text { Discount }&\text {Profit }\\\text { CG-12520 } & \text { Claire } & \text { Gute } & \$ 261.96 & 2 & 0 & \$ 41.91 \\\text { DV-13045 } & \text { Darrin } & \text { VanHuff } & \$ 14.62 & 2 & 0 & \$ 16.87 \\\text { SO-20335 } & \text { Sean } & \text { O'Donnell } & \$ 9557.58 & 5 & 0.45 & \$ (383.03) \\\text { BH-11710 } & \text { Brosina } & \text { Hoffman } & \$ 48.86 & 7 & 0 & \$ 14.17 \\\text { AA-10480 } & \text { Andrew } & \text { Allen } & \$ 25.55 & 3 & 0.2 & \$ 5.44 \\\text { IM-15070 } & \text { Irene } & \text { Maddox } & \$ 407.98 & 3 & 0.2 & \$ 132.59 \\\text { HP-14815 } & \text { Harold } & \text { Pawlan } & \$ 68.81 & 5 & 0.8 & \$(123.86) \\\text { PK-19075 } & \text { Pete } & \text { Kriz } & \$ 665.88 & 6 & 0 & \$ 13.32 \\\text { AG-10270 } & \text { Alejandro Grove } & \$ 55.50 & 2 & 0 & \$ 9.99 \\\text { ZD-21925 } & \text { Zuschuss } & \text { Donatelli } & \$ 8.56 & 2 & 0 & \$ 2.48\end{array}$ ?
?

A)?The last names must be sorted from A to Z.
B)?The last names must be sorted from Z to A.
C)?The last names must be sorted from the earliest to the latest that has been added to the list.
D)?James should use the Sort function to organize the data into order of sales.

Question 79

In a survey of patients in a local hospital, 62.42% of the respondents indicated that the health care providers needed to spend more time with each patient. What is the sample for the population being studied? ​​

A)​All patients in a local hospital
B)All survey respondents
C)Hospital patients
D)​Cannot be determined from the information given

Question 80

Below are the data for the number of days that it took Wyche Accounting to perform audits in the last quarter of last year.
​
56, 42, 37, 29, 45, 51, 30, 25, 34, 57
​
What is(are) the mode(s) number of days that it took Wyche Accounting to perform audits in the last quarter of last year?​