We included HMH Into Math Grade 8 Answer Key PDF Module 8 Review to make students experts in learning maths.

Vocabulary

Choose the correct term from the Vocabulary box.

Vocabulary
outlier
cluster
trend line
association
scatter plot
domain

Question 1.
A(n) ____________ is a set of closely grouped data points.
Cluster,

Explanation:
A(n) cluster is a set of closely grouped data points or
A set of closely grouped data points.

Question 2.
A(n) _________ is a data point that is far from the other points on the graph of a set of paired data.
Outlier,

Explanation:
A(n) outlier is a data point that is far from the other points on the graph of a set of paired data.
An outlier for a scatter plot is the point or points that are farthest from the regression line.
There is at least one outlier on a scatter plot in most cases, and there is usually only one outlier.

Question 3.
A(n) ____________ is a description of the relationship between two data sets.
Association,

Explanation:
A(n) association is a description of the relationship between two data sets.

Question 4.
A(n) _____________ is a line on a scatter plot that helps show a linear association.
Trend line

Explanation:
A(n) trend line is a line on a scatter plot that helps show a linear association.
Trend lines are lines used to approximate the general shape of a scatter plot. A positive trend line tells us the scatter plot has a positive correlation.
A negative trend line tells us the scatter plot has a negative correlation.

Question 5.
A(n) ____________ is a graph that uses points to show how two data sets are related.
Scatter plot,

Explanation:
A(n) scatter plot is a graph that uses points to show how two data sets are related.

Concepts and Skills

Question 6.
Use Tools The scatter plot shows the relationship between the numbers of hours players spent playing a video game and their high scores. Draw a trend line for the scatter plot. State what strategy and tool you will use to answer the question, explain your choice, and then find the answer.

Positive association, Linear,

Explanation:
Given the scatter plot shows the relationship between the numbers of hours players spent playing a video game and their high scores. Drawn a trend line for the scatter plot.The strategy and tool I will use is it is a poisitve. As the number of hours players spent playing
a video game increased they are scoring high, it is a positive linear association.

Question 7.
The scatter plot shows the ages of the used cars at a car dealership and the numbers of miles the cars have been driven. Select all statements that correctly interpret the scatter plot.

(A) The data show a positive association.
(B) The data point at (9, 105) is an outlier.
(C) The data show a negative association.
(D) The data show a nonlinear association.
(E) There is a cluster of data points near (2, 23).
(A) The data show a positive association and
(E) There is a cluster of data points near (2, 23),

Explanation:
Given a scatter plot shows the ages of the used cars at a car dealership and the numbers of miles the cars have been driven. Selected all statements that correctly interpret the scatter plot as
(A) The data show a positive association because as the ages of the used cars at a car dealership increased, the number of miles of the cars have been driven also increased, and (E) There is a cluster of data points near (2, 23),
Yes we have almost 4 data points at (2, 23).

Question 8.
The scatter plot shows data for students in Brenna’s class. A trend line for the data is y = 0.054x – 0.099.

Use the trend line to predict how long, to the nearest minute, it would take a student in Brenna’s class to walk 5 miles.
_____________ minutes
94.42 almost 94 minutes,

Explanation:
Given a scatter plot shows data for students in Brenna’s class. A trend line for the data is y = 0.054x – 0.099. Using the trend line to
predict how long, to the nearest minute, it would take a student in Brenna’s class to walk 5 miles is as y = 5 miles substituting in the equation we get 5 = 0.054x – 0.099,
5 + 0.099 = 0.054x,
0.054x = 5.099, So x = 5.099/0.054 = 94.42 almost nearly 94, So for 5 miles walk it will take nearly 94 minutes.

Question 9.
Calista surveyed eight classmates about the numbers of texts they sent and received in the past 3 hours. The table shows her results. Use the data set from the table to complete the scatter plot.

Explanation:
Given Calista surveyed eight classmates about the numbers of texts they sent and received in the past 3 hours.
The table showed her results. Used the data set from the table and completed the scatter plot as shown above.

A good trend line for the data in the table is y = -0.0036x + 70.64. Use this trend line for Problems 10 and 11

Question 10.
What does the number -0.0036 in the trend line represent in this situation?
-0.0036 is the slope of the trend line,
The slope is negative decreasing,

Explanation:
Slope describes the steepness of a line.
The slope of any line remains constant along the line.
The slope can also tell us information about the direction of the line on the coordinate plane.
Slope can be calculated either by looking at the graph of a line or by using the coordinates of any two points on a line. Here the line is decreasing if it goes down from left to right.
The slope is negative i.e. m<0.

Question 11.
What does the number 70.64 in the trend line represent?