Transcript Section 2.4 Representing Data Standard I&E: 1a Mastering Concepts: 50(69-71) Terms: 43 Homework: Cornell Notes: 2.4 Section Assessment: 45(45-48) Mastering Problems: 50 (86-87) 6 stamps.

Section 2.4
1
Representing Data
Standard I&E: 1a
Mastering Concepts: 50(69-71)
Terms: 43
Homework:
Cornell Notes: 2.4
Section Assessment: 45(45-48)
Mastering Problems: 50 (86-87)
6 stamps
2
Section 2.4 Representing Data
• Create graphics to reveal
patterns in data.
Section 2-4
independent variable: the
variable that is changed
during an experiment
• Interpret graphs.
graph
Graphs visually depict data, making it easier
to see patterns and trends.
Mastering Concepts: 50(69-71)
69. Which type of graph would you choose to depict data
on how many households heat with gas, oil, or
electricity? Explain. (2.4)
A bar graph could be used with the method of heating on
the x-axis and the number of households on the y-axis.
If the data include all the households for a region,
relative numbers could be converted to a percentage
and expressed as a circle graph.
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Mastering Concepts: 50(69-71)
70. Which type of graph would you choose to depict
changes in gasoline consumption over a period of ten
years? Explain. (2.4)
line or bar graph because they can show how
consumption varies with time
71. How can you find the slope of a line graph? (2.4)
Choose two points on the line. Divide the difference in
the y values by the difference in the x values.
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Section 2.4 Assessment
page 45
45. Explain why graphing can be an important
tool for analyzing data.
It provides visual information about relationships
between variables, relative amounts, or parts of a
whole.
46. What type of data can be displayed on a
circle graph? On a bar graph?
parts of a whole; how a quantity varies with a
factor
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Section 2.4 Assessment
page 45
47. If a linear graph has a negative slope, what
can you say about the dependent variable?
It decreases in value as the independent
variable increases.
48. When can the slope of a graph represent
density?
when mass is the y value and volume is the x
value
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Problem-solving Lab
Stopping distance
(m)
18
32
49
68
92
Speed (m/s)
11
16
20
25
29
8
How does speed affect stopping distance?
Distance (m)
100
80
60
40
20
0
0
10
Speed
(m/s)
20
30
9
Graphing
•
Section 2-4
A graph is a visual display of data that makes trends easier to see than in a table.
Graphing (cont.)
•
Section 2-4
A circle graph, or pie chart, has wedges that visually represent
percentages of a fixed whole.
Graphing (cont.)
•
Section 2-4
Bar graphs are often used to show how a quantity varies across
categories.
Graphing (cont.)
Section 2-4
• On line graphs, independent variables are plotted on the x-axis
and dependent variables are plotted on the y-axis.
Graphing (cont.)
Section 2-4
• If a line through the points is straight, the
relationship is linear and can be analyzed
further by examining the slope.
Interpreting Graphs
Section 2-4
• Interpolation is reading and estimating
values falling between points on the
graph.
• Extrapolation is estimating values outside
the points by extending the line.
Interpreting Graphs (cont.)
Section 2-4
• This graph shows important ozone measurements
and helps the viewer visualize a trend from two
different time periods.
End of Section 2-4