Question 1

Use the following Table to answer the  Questions: $\begin{array} { | l | c | c | c | c | c | c | c | } 
\hline \begin{array} { l } 
\text { Hours spent } \
\text { partying per } \
\text { week } ( x )
\end{array} & 10 & 40 & 0 & 5 & 60 & 20 & 12 \
\hline \text { GPA } ( y ) & 3.4 & 0.5 & 3.9 & 3.7 & 4.0 & 1.3 & 3.1 \
\hline
\end{array}$
-What is the slope of the regression line?

Accepted Answer

The answer of Use the following Table to answer the...

Question 2

Use the following scatterplot to answer the Questions: 
-What conclusions can you reach if you hear 18 chirps a minute?

Accepted Answer

A)  The temperature is about 87. 
B)  The temperature is about 90. 
C)  This is not a valid answer; 18 is not possible. 
D)  The data of the scatterplot are not valid.

Question 3

A data set has $\bar{x} $ = 5, $\bar{y}$ = 10, Sx = 2, Sy = 3 . What is the standardized value of $x$ =7?

Accepted Answer

A)  1 
B) -1 
C)  2 
D) -2

Question 4

If the least-squares regression line is y = 3x − 5, the value y = 1 is predicted for what value of x?

Accepted Answer

A)  0 
B)  1 
C)  2 
D)  6

Question 5

Suppose a scatterplot shows four clusters at each corner of the plot. What can you say about the feasibility of using a least-squares regression line to describe these data?

Accepted Answer

The answer of Suppose a scatterplot shows four clusters at...

Question 6

Can outliers significantly affect the least-squares regression line?

Accepted Answer

The answer of Can outliers significantly affect the least-squares regression...

Question 7

A university admissions counselor wishes to predict the performance of freshmen by considering their SAT scores. Which variable, freshman GPA or SAT score, would be the explanatory variable in a least squares regression equation?

Accepted Answer

A)  freshman GPA 
B)  SAT score

Question 8

Use the following scatterplot to answer the Questions: 
-What can you say about the slope of the least-squares regression line?

Accepted Answer

A)  The slope is zero. 
B)  The slope is positive. 
C)  The slope is negative. 
D)  The slope varies.

Question 9

Is it possible for the correlation for a scatterplot to change dramatically when a single point is moved?

Accepted Answer

The answer of Is it possible for the correlation for...

Question 10

If the units of measurement change to larger units, then the correlation:

Accepted Answer

A)  becomes larger. 
B)  becomes smaller. 
C)  does not change. 
D)  Can either become larger or smaller.

Question 11

Below is the scatterplot for data collected on two variables. Would a least-squares regression equation be useful in describing the relationship between the variables? Why or why not?

Accepted Answer

The answer of Below is the scatterplot for data collected...

Question 12

Use the table below to answer the following Questions . $\begin{array} { l l l l l l l l l l l } 
\text { Temperature in degrees } F ( y )& 70 & 72 & 74 & 75 & 81 & 82 & 83 & 84 & 89 & 93 \
\text { Chirps per second } ( x ) & 15 & 15 & 15 & 16 & 17 & 17 & 16 & 17 & 19 & 20
\end{array}$
-What is the correlation between the variables?

Accepted Answer

A)  about 0.99 
B)  about 0.94 
C)  about 0.70 
D)  about 0.50

Question 13

Use the table below to answer the following Questions . $\begin{array} { l l l l l l l l l l l } 
\text { Temperature in degrees } F ( y )& 70 & 72 & 74 & 75 & 81 & 82 & 83 & 84 & 89 & 93 \
\text { Chirps per second } ( x ) & 15 & 15 & 15 & 16 & 17 & 17 & 16 & 17 & 19 & 20
\end{array}$
-Let x = number of chirps per second and y = temperature. How many points are above the regression line?

Accepted Answer

A)  4 
B)  5 
C)  6 
D)  None of the above.

Question 14

Max is collecting baseball cards. He has 65 cards that his aunt gave him for his birthday, and he buys 20 more each week. The total number y of cards that Max has after x weeks is given by which of the following equations?

Accepted Answer

A)  y = 20 + 65x 
B)  y = 65 + 20x 
C)  y = 20 + x 
D)  y = 85x

Question 15

A data set has $\bar{x}$ = 2, $\bar{y}$ = 7, Sx = 3, Sy = 3 r = 0.95 Which of the following point is on the least-squares regression line?

Accepted Answer

A)  (2,3) 
B)  (2,7) 
C)  (3,3) 
D)  (7,3)

Question 16

Use the following scatterplot to answer the  Questions:

-What can you say about the correlation of the data?

Accepted Answer

A)  The correlation is nearly 1. 
B)  The correlation is nearly −1. 
C)  The correlation is nearly 0. 
D)  The data have no correlation.

Question 17

Use the following data to answer the Questions: $\begin{array} { r r } 
\underline { X }  & \underline { Y } \
66 & 118 \
50 & 99 \
73 & 120 \
69 & 121 \
72 & 123 \
65 & 108 \
62 & 111
\end{array}$
-What type of association exists between the variables on the scatterplot?

Accepted Answer

The answer of Use the following data to answer the...

Question 18

A typing service keeps data on the number of pages (x) in a manuscript and the length of time (y) (in hours) it takes to complete the typing. The least-squares regression line for the data is given by y = 20 + 0.273x. Use this to predict the amount of hours needed to type a 40-page manuscript.

Accepted Answer

A)  810.92 
B)  60.273 
C)  30.92 
D)  16.38

Question 19

If two variables named x and y have a strong positive association, then:

Accepted Answer

A)  increasing x will cause y to increase. 
B)  making x positive will make y positive. 
C)  doubling x will cause y to double. 
D)  changes in x do not necessarily cause changes in y.

Question 20

If the x and y coordinates of a scatterplot are exchanged, the intercept of the regression line:

Accepted Answer

A)  remains unchanged. 
B)  changes to its opposite. 
C)  changes to its reciprocal. 
D)  None of the above.

Exam 6: Exploring Data: Relationships

Use the following scatterplot to answer the Questions: -What conclusions can you reach if you hear 18 chirps a minute?

A data set has $\bar{x}$ = 5, $\bar{y}$ = 10, S_x = 2, S_y = 3 . What is the standardized value of $x$ =7?

If the least-squares regression line is y = 3x − 5, the value y = 1 is predicted for what value of x?

Suppose a scatterplot shows four clusters at each corner of the plot. What can you say about the feasibility of using a least-squares regression line to describe these data?

Can outliers significantly affect the least-squares regression line?

A university admissions counselor wishes to predict the performance of freshmen by considering their SAT scores. Which variable, freshman GPA or SAT score, would be the explanatory variable in a least squares regression equation?

Use the following scatterplot to answer the Questions: -What can you say about the slope of the least-squares regression line?

Is it possible for the correlation for a scatterplot to change dramatically when a single point is moved?

If the units of measurement change to larger units, then the correlation:

Below is the scatterplot for data collected on two variables. Would a least-squares regression equation be useful in describing the relationship between the variables? Why or why not?

Max is collecting baseball cards. He has 65 cards that his aunt gave him for his birthday, and he buys 20 more each week. The total number y of cards that Max has after x weeks is given by which of the following equations?

A data set has $\bar{x}$ = 2, $\bar{y}$ = 7, S_x = 3, S_y = 3 r = 0.95 Which of the following point is on the least-squares regression line?

Use the following scatterplot to answer the Questions: -What can you say about the correlation of the data?

Use the following data to answer the Questions: $\begin{array} { r r } \underline { X } & \underline { Y } \\66 & 118 \\50 & 99 \\73 & 120 \\69 & 121 \\72 & 123 \\65 & 108 \\62 & 111\end{array}$ -What type of association exists between the variables on the scatterplot?

A typing service keeps data on the number of pages (x) in a manuscript and the length of time (y) (in hours) it takes to complete the typing. The least-squares regression line for the data is given by y = 20 + 0.273x. Use this to predict the amount of hours needed to type a 40-page manuscript.

If two variables named x and y have a strong positive association, then:

If the x and y coordinates of a scatterplot are exchanged, the intercept of the regression line:

Exam 6: Exploring Data: Relationships

Use the following scatterplot to answer the Questions: -What conclusions can you reach if you hear 18 chirps a minute?

A data set has xˉ\bar{x} xˉ = 5, yˉ\bar{y}yˉ​ = 10, Sx = 2, Sy = 3 . What is the standardized value of xxx =7?

If the least-squares regression line is y = 3x − 5, the value y = 1 is predicted for what value of x?

Suppose a scatterplot shows four clusters at each corner of the plot. What can you say about the feasibility of using a least-squares regression line to describe these data?

Can outliers significantly affect the least-squares regression line?

A university admissions counselor wishes to predict the performance of freshmen by considering their SAT scores. Which variable, freshman GPA or SAT score, would be the explanatory variable in a least squares regression equation?

Use the following scatterplot to answer the Questions: -What can you say about the slope of the least-squares regression line?

Is it possible for the correlation for a scatterplot to change dramatically when a single point is moved?

If the units of measurement change to larger units, then the correlation:

Below is the scatterplot for data collected on two variables. Would a least-squares regression equation be useful in describing the relationship between the variables? Why or why not?

Max is collecting baseball cards. He has 65 cards that his aunt gave him for his birthday, and he buys 20 more each week. The total number y of cards that Max has after x weeks is given by which of the following equations?

A data set has xˉ\bar{x}xˉ = 2, yˉ\bar{y}yˉ​ = 7, Sx = 3, Sy = 3 r = 0.95 Which of the following point is on the least-squares regression line?

Use the following scatterplot to answer the Questions: -What can you say about the correlation of the data?

A typing service keeps data on the number of pages (x) in a manuscript and the length of time (y) (in hours) it takes to complete the typing. The least-squares regression line for the data is given by y = 20 + 0.273x. Use this to predict the amount of hours needed to type a 40-page manuscript.

If two variables named x and y have a strong positive association, then:

If the x and y coordinates of a scatterplot are exchanged, the intercept of the regression line:

A data set has $\bar{x}$ = 5, $\bar{y}$ = 10, S_x = 2, S_y = 3 . What is the standardized value of $x$ =7?

A data set has $\bar{x}$ = 2, $\bar{y}$ = 7, S_x = 3, S_y = 3 r = 0.95 Which of the following point is on the least-squares regression line?