Transcript Lesson 71, Scatter Plots

Warm Up
1.
The constant 𝑚 in the _____________________ form 𝑦 = 𝑚𝑥 + 𝑏
is the slope of the line.
2.
The equation of a line is 𝑦 = −2𝑥 + 6. What is the slope of the
line?
3.
Write the equation 𝑥 − 2𝑦 = 4 in slope intercept form.
4.
Write an equation in slope intercept form for a line with a
slope of
3
8
and a y-intercept of −4.
Lesson 71:
Scatter Plots
PROBABILITY AND STATISTICS
Scatter Plots and Lines of Best Fit

Scatter plot: a graph that relates two sets of data with plotted
ordered pairs

Trend line: a line on a scatter plot that shows the relationship
between two sets of data

Correlation: a measure of the strength and direction of the
association between data sets or variables

The closer the points are clustered together, the stronger the correlation

Positive correlation: occurs when data values for both variables
increase

Negative correlation: occurs when data values for one variable
increase while data values for the other variable decrease
Example
Use the data in the table to make a scatter plot, draw a trend line, and
find an equation for the trend line.
X
1
2
3
4
5
6
Y
4
10
12
18
23
29
Your Turn
Use the data in the table to make a scatter plot, draw a trend line, and
find an equation for the trend line.
X
1
2
3
4
5
6
Y
14
27
43
53
70
85
Example
State whether there is a positive correlation, a negative correlation, or
no correlation between the data values.
a.
b.
7
X
10
9
8
7
6
5
4
3
2
6
Y
60
63
72
75
77
81
83
89
92
5
4
3
2
c.
height and shoe size
d.
Date of birth and shoe size
1
0
0
2
4
6
8
Your Turn
State whether there is a positive correlation, a negative correlation, or
no correlation between the data values.
a.
b.
9
8
Outdoor temperature and the
number of sweaters sold
7
6
c.
5
4
3
X
2
5
6
8
9
11
13
16
20
Y
10
12
13
15
17
20
21
24
26
2
1
0
0
2
4
6
8
d.
Hair color and height
Example
Match each situation with the scatter plot that models it best.
a.
Number of trucks on the road and number of days in a month
b.
Time spent driving and distance traveled
c.
Number of months you own a car and the value of the car
8
7
6
5
4
3
2
1
0
7
9
8
7
6
5
4
3
2
1
0
6
5
4
3
2
1
0
0
2
Graph 1
4
6
0
5
Graph 2
10
0
5
Graph 3
10
Your Turn
Match each situation with the scatter plot that models it best.
a.
Time spent exercising and calories burned
b.
Number of dishes washed and ounces of detergent in a bottle
c.
Population of a country and number of states in the country
8
7
6
5
4
3
2
1
0
8
7
6
5
4
3
2
1
0
8
7
6
5
4
3
2
1
0
0
5
Graph 1
10
0
5
Graph 2
10
0
5
Graph 3
10
Homework Questions
Homework Questions
Correcting Homework

Be kind.

If the paper in front of you has no work shown, return it to its owner.

If the paper in front of you is not in pencil or black ink, return it to its
owner.

If the paper in front of you is not complete, return it to its owner.

Remember you are filling out the score sheet for the person that
you are correcting.

Be sure to write “C.B. ____________” with your name on the paper
you graded and on the score sheet.
Homework

1st and 2nd hour: Lesson 71 Practice A-B, D-L, #1-3, 6-9, 11-13, 18-21,
24-26, 29

3rd hour: Lesson 71 Practice A-B, D-L, #1, 11-13