7th Grade Math

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More Statistical Displays

PART A B C

Multi-Part

Lesson 4

GLE 0706.5.1

Collect, organize, and analyze

both single- and two-variable

data. GLE 0706.5.2 Select,

create, and use appropriate

graphical representations of

data. Also addresses

GLE 0706.1.4, SPI 0706.5.1,

SPI 0706.5.2.

534 Statistical Displays

Main Idea

Analyze line graphs

and scatter plots to

make predictions and

conclusions.

Vocabulary

scatter plot

line of best fit

Scatter Plots and Lines of Best Fit

• Pour 1 cup of water into a Number of
  Marbles
  0
  5
  10
  15
  20

Height of

drinking glass. Water (cm)

• Measure the height of the
  water and record it in a table
  like the one shown.


• Place 5 marbles in the glass.
  Measure the height of the
  water. Record.


• Continue adding marbles,
  5 at a time, until there are
  20 marbles in the glass.
  After each time, measure
  and record the height of
  the water.

1. By how much did the water’s height change after each addition
   of marbles?


2. Predict the height of the water when 30 marbles are in the
   drinking glass. Explain how you made your prediction.


3. Test your prediction by placing 10 more marbles in the glass.


4. Graph the ordered pairs you recorded in the table on a
   coordinate plane.

A scatter plot shows the relationship between a set of data with two

variables graphed as ordered pairs on a coordinate plane. Like line

graphs, scatter plots are useful for making predictions because they

show trends in data.

Types of Relationships

Positive Relationship Negative Relationship No Relationship

y

O x

y

O x

y

O x

5

10

15

20

V

s

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