Reading Tables and Graphs
7th Grade Science Department
Data Tables
• The independent variable
always goes on the left side
of a data table
• The dependent variable
always goes on the right side
of a data table
Drawing Conclusions from Data
Tables
Number of Sit-ups
Heart Rate (beats-per-minute)
0
10
20
30
40
48 bpm
50 bpm
54 bpm
63 bpm
66 bpm
Independent Variable:
Number of sit ups
Dependent Variable:
Heart rate
Conclusion:
The more sit ups the faster your heart rate.
Bar Graphs
• Use a bar graph when you have qualitative
data as your independent variable
• The independent variable always goes on the
x-axis
• The dependent variable always goes on the
y-axis
Drawing Conclusions from Bar Graphs
70
Absorbency (mL)
60
50
40
30
20
10
0
Bounty
Brawny
Viva
Sparkle
Brand of Paper Towel
Independent Variable:
Brand of paper towel
Dependent Variable:
Absorbency
Conclusion:
Viva paper towels absorbs more liquid.
Scott
Line Graphs
•Use a line graph when you have all
quantitative data
•The independent variable always goes
on the x-axis
•The dependent variable always goes on
the y-axis
Drawing Conclusions from
Line Graphs
Independent Variable: Temperature
Dependent Variable:
Conclusion:
Frog Croaks
The higher the temperature the higher the croaks per minute.
D ependent
R esponding
Y - axis
M anipulated
I ndependent
X - axis
Practice
Problems!
Type of Ball
Height of bounce (cm)
Golf Ball
54 cm
Tennis Ball
48 cm
Ping Pong Ball
21 cm
Baseball
9 cm
Independent Variable: Type of ball
Dependent Variable: Height of bounce
Conclusion: Golf ball has the highest bounce
Independent Variable: Time (weeks)
Dependent Variable: Height
Conclusion: As time goes by the height of plant increases
Considered this hypothesis: “The amount of salt in water in a solution
will increase the rate at which water will leave the cells of a potato
placed in the solution.” An experiment to test the hypothesis is
summarized in the table.
Group
Surface
Area of
Potato
Temperature
of Water
Time in
Water
Percent of
Salt in
Water
#1
10 cm2
25°C
6 hours
0%
#2
10 cm2
25°C
6 hours
10%
#3
10 cm2
25°C
6 hours
20%
#4
10 cm2
25°C
6 hours
30%
Independent Variable:
Dependent Variable:
Control Variables
Percent of salt in water
Rate that water leaves the cells
Surface area, water temperature, and time in water
Independent Variable: Temperature
Dependent Variable: Volume of CO2
Conclusion: Highest levels of CO2 occurs between 30° and 45°C
Independent Variable: Time
Dependent Variable: Number of bacterial cells
Conclusion: As time increases so does the number of bacterial cells but levels off after
32 hours