Question 1

The coefficient of determination lies between 0 and 1.

Accepted Answer

A) True 
 B)False

Question 2

A courier company is reviewing their delivery times. The following descriptive statistics relates to this courier company. The mean time for package delivery is 5 hours, the first quartile is 4 hours, the third quartile is 17 hours. This means that 50% of deliveries take more than 5 hours?

Accepted Answer

A) True 
 B)False

Question 3

Which of the following statements is true? $\begin{array}{|l|l|} \hline A&\text { When the distribution is skewed to the left, mean $ > $ median $ > $ mode.}\ \hline B&\text {When the distribution is skewed to the right, mean $ < $ median $ < $ mode. }\ \hline C&\text {When the distribution is symmetric and unimodal, mean $ = $ median $ = $ mode. }\ \hline D&\text { When the distribution is symmetric and bimodal, mean $ = $ median $ = $ mode.}\ \hline \end{array}$

Accepted Answer

The answer of Which of the following statements is true?...

Question 4

The average score for a class of 30 students was 75. The 20 male students in the class averaged 70. The female students in the class averaged: $\begin{array}{|l|l|}
\hline  A&\text { 75}\
\hline  B&\text { 85}\
\hline  C&\text {65 }\
\hline  D&\text {70 }\
\hline  E&\text {80 }\
\hline 
\end{array}$

Accepted Answer

The answer of The average score for a class of...

Question 5

The range is considered the weakest measure of variability.

Accepted Answer

A) True 
 B)False

Question 6

The coefficient of variation gives an indication of the magnitude of the standard deviation relative to the mean.

Accepted Answer

A) True 
 B)False

Question 7

Which of the following statements best describes the mean of a data set? $\begin{array}{|l|l|}
\hline  A&\text {The mean is a measure of spread. }\
\hline  B&\text {The mean is a measure of central location, defined as the middle value in a sorted set of data. }\
\hline  C&\text { he mean is a measure of central location, calculated by summing all observations in a data set divided}\
&\text {by the number of observations in the data set. }\
\hline  D&\text {The mean is a measure of central location, defined as the observation in a data set with }\
&\text { the highest frequency.}\
\hline 
\end{array}$

Accepted Answer

The answer of Which of the following statements best describes...

Question 8

Monthly rent data in dollars for a sample of 10 one-bedroom apartments in Perth are given below: $$\begin{array} { | l | l | l | l | l | l | l | l | l | l| } 
\hline 220 & 200 & 230 & 215 & 235 & 250 & 260 & 210 & 265 & 250 \
\hline
\end{array}$$ a. Compute the sample monthly average rent.
b. Compute the sample median.
c. What is the mode?

Accepted Answer

a. mean = $233.50
b.

Question 9

The following data are the heights (in cm) of the 25 students in a business statistics class: $$\begin{array} { | l | l | l | l | l | l | l | l | l | l | } 
\hline 164 & 148 & 137 & 157 & 173 & 156 & 177 & 172 & 169 & 165 \
\hline 145 & 168 & 163 & 162 & 174 & 152 & 156 & 168 & 154 & 151 \
\hline 174 & 146 & 134 & 140 & 171 & & & & & \
\hline
\end{array}$$ a. Compute the range of the data.
b. Compute the range approximation to the standard deviation of the data. (Hint: S $\approx$ Range/4.)

Accepted Answer

a. range =

Question 10

In a symmetric distribution, the mean is the most used measure of central location for quantitative data.

Accepted Answer

A) True 
 B)False

Question 11

The relative frequency histogram for the age (in years) of a sample of 25 employees from a government department, is given below.   Explain what the best measure of variability is.

Accepted Answer

The distribution of ages is po

Question 12

The following data represent the ages (in years) of a sample of 25 employees from a government
department: $\begin{array}{|l|l|l|l|l|l|l|l|l|l|}
\hline 31 & 43 & 56 & 23 & 49 & 42 & 33 & 61 & 44 & 28 \
\hline 48 & 38 & 44 & 35 & 40 & 64 & 52 & 42 & 47 & 39 \
\hline 53 & 27 & 36 & 35 & 20 & & & & & \
\hline
\end{array}$ Find the coefficient of variation.

Accepted Answer

The answer of The following data represent the ages (in...

Question 13

The following data represent the weights (in kilograms) of a sample of 30 horses: Weight
$\begin{array} { l } 
165 \
175 \
150 \
155 \
173 \
149 \
145 \
153 \
153 \
153 \
152 \
145 \
164 \
143 \
170 \
175 \
148 \
174 \
171 \
156 \
166 \
168 \
152 \
150 \
173 \
168 \
146 \
155 \
172 \
159
\end{array}$ Determine the location and value of the upper quartile of the weights.

Accepted Answer

L₇₅= 23.25,

Question 14

A basketball player has the following points for seven games: 20, 25, 32, 18, 19, 22, 30. Compute the following measures of central location and variability:
a. mean.
b. median.
c. standard deviation.
d. coefficient of variation.

Accepted Answer

a. x = 23.714
b. med

Question 15

If the coefficient of correlation r = +1, then the best-fit linear equation will actually be satisfied by all of the data points.

Accepted Answer

A) True 
 B)False

Question 16

The following data represent the ages (in years) of a sample of 25 employees from a government
department: $\begin{array}{|l|l|l|l|l|l|l|l|l|l|}
\hline 31 & 43 & 56 & 23 & 49 & 42 & 33 & 61 & 44 & 28 \
\hline 48 & 38 & 44 & 35 & 40 & 64 & 52 & 42 & 47 & 39 \
\hline 53 & 27 & 36 & 35 & 20 & & & & & \
\hline
\end{array}$ Compute the sample variance and sample standard deviation.

Accepted Answer

s² = 124.83

Question 17

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: $\begin{array}{|l|l|l|l|l|l|l|}
\hline 26.5 & 23.5 & 29.7 & 24.8 & 21.1 & 24.3 & 20.4 \
\hline 22.7 & 27.2 & 23.7 & 24.1 & 24.8 & 28.2 & \
\hline
\end{array}$ Compute the 90th percentile.

Accepted Answer

= 12.6.
90th percent

Question 18

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: $\begin{array}{|l|l|l|l|l|l|l|}
\hline 26.5 & 23.5 & 29.7 & 24.8 & 21.1 & 24.3 & 20.4 \
\hline 22.7 & 27.2 & 23.7 & 24.1 & 24.8 & 28.2 & \
\hline
\end{array}$ Compute the range.

Accepted Answer

The answer of The following data represent the salaries (in...

Question 19

Chebyshev's theorem applies only to data sets that have a mound-shaped distribution.

Accepted Answer

A) True 
 B)False

Question 20

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: $\begin{array}{|l|l|l|l|l|l|l|}
\hline 26.5 & 23.5 & 29.7 & 24.8 & 21.1 & 24.3 & 20.4 \
\hline 22.7 & 27.2 & 23.7 & 24.1 & 24.8 & 28.2 & \
\hline
\end{array}$ Consider the following population of measurements: $$\begin{array} { | l | l | l | l | l | l | l | l | l | l | } 
\hline 162 & 152 & 177 & 157 & 184 & 176 & 165 & 181 & 170 & 163 \
\hline
\end{array}$$ a. Compute the mean.
b. Compute the median.
c. Compute the variance and the standard deviation.

Accepted Answer

a. 168.7.

Exam 5: Numerical Descriptive Measures

The coefficient of determination lies between 0 and 1.

A courier company is reviewing their delivery times. The following descriptive statistics relates to this courier company. The mean time for package delivery is 5 hours, the first quartile is 4 hours, the third quartile is 17 hours. This means that 50% of deliveries take more than 5 hours?

The average score for a class of 30 students was 75. The 20 male students in the class averaged 70. The female students in the class averaged: A 75 B 85 C 65 D 70 E 80

The range is considered the weakest measure of variability.

The coefficient of variation gives an indication of the magnitude of the standard deviation relative to the mean.

Monthly rent data in dollars for a sample of 10 one-bedroom apartments in Perth are given below: 220 200 230 215 235 250 260 210 265 250 a. Compute the sample monthly average rent. b. Compute the sample median. c. What is the mode?

In a symmetric distribution, the mean is the most used measure of central location for quantitative data.

The relative frequency histogram for the age (in years) of a sample of 25 employees from a government department, is given below. Explain what the best measure of variability is.

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Find the coefficient of variation.

The following data represent the weights (in kilograms) of a sample of 30 horses: Weight 165 175 150 155 173 149 145 153 153 153 152 145 164 143 170 175 148 174 171 156 166 168 152 150 173 168 146 155 172 159 Determine the location and value of the upper quartile of the weights.

A basketball player has the following points for seven games: 20, 25, 32, 18, 19, 22, 30. Compute the following measures of central location and variability: a. mean. b. median. c. standard deviation. d. coefficient of variation.

If the coefficient of correlation r = +1, then the best-fit linear equation will actually be satisfied by all of the data points.

The following data represent the ages (in years) of a sample of 25 employees from a government department: 31 43 56 23 49 42 33 61 44 28 48 38 44 35 40 64 52 42 47 39 53 27 36 35 20 Compute the sample variance and sample standard deviation.

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: 26.5 23.5 29.7 24.8 21.1 24.3 20.4 22.7 27.2 23.7 24.1 24.8 28.2 Compute the 90th percentile.

The following data represent the salaries (in thousands of dollars) of a sample of 13 employees of a firm: 26.5 23.5 29.7 24.8 21.1 24.3 20.4 22.7 27.2 23.7 24.1 24.8 28.2 Compute the range.

Chebyshev's theorem applies only to data sets that have a mound-shaped distribution.

What Is Statistics

Types of Data, Data Collection and Sampling

Graphical Descriptive Methods Nominal Data

Graphical Descriptive Techniques Numerical Data

Probability

Random Variables and Discrete Probability Distributions

Continuous Probability Distributions

Statistical Inference: Introduction

Sampling Distributions

Estimation: Describing a Single Population

Estimation: Comparing Two Populations

Hypothesis Testing: Describing a Single Population

Hypothesis Testing: Comparing Two Populations

Inference About Population Variances

Analysis of Variance

Additional Tests for Nominal Data: Chi-Squared Tests

Simple Linear Regression and Correlation

Multiple Regression

Model Building

Nonparametric Techniques

Statistical Inference: Conclusion

Time-Series Analysis and Forecasting

Index Numbers

Decision Analysis

Filters