Name: ______Date: ______Period: ______
Reading and Creating Graphs and Charts
You've seen them everywhere: graphs and charts that represent and organize information.
Pie charts and bar graphs are fairly common. Here are two examples: one is a pie chart and one is a bar graph. They are both representing the same information: The number of students in each grade at Dixon High.
· Which one do you think represents this particular data better?
So, what is the best way to learn how to read and interpret graph? PRACTICE!
Carefully read the graphs below and answer the questions.
1) What does this graph represent?
a) Kilowatts used by appliances
b) Hours appliance used per day
c) Total electricity used per year
d) Hours appliances used per month
2) What do the numbers in the vertical axis represent?
a) Hours in a day
b) Days in a week
c) Types of appliances
d) Amount of electricity used
3) Which appliance is used the most? What about the least?
Here is an example of a pie chart. It was created with data representing the expenses of a corporate company.
ABC Company’s Yearly Expenses by Category
4) Which category represents about 25% of all spending?
5) Which category represents the largest share of the expenses?
6) Which two categories together represent about 50% of all spending?
7) Doubling the operations expenses would make them approximately equal to what other category?
8) How many expense categories are represented by the chart?
Now, you can make your first attempt at creating a graph on your own.
11. Using the following data, answer the questions below.
Students / Number of BBall Shots MadeNicholas / 10
Eric / 8
Emma / 14
Bailey / 4
Madison / 8
Suzie / 3
A. What is the dependent variable and why?
B. What is the independent variable and why?
c. Now create a bar graph that represents the data.
· Do not forget to label ALL parts of the graph and to put a title!
12. Using the following data, answer the questions below.
Depth in meters / Number of Bubbles / minute2 / 29
5 / 36
10 / 45
16 / 32
25 / 20
30 / 10
A. What is the dependent variable and why?
B. What is the independent variable and why?
c. Now create a line graph that represents the data.
· Do not forget to label ALL parts of the graph and to put a title!
13. Using the following data, answer the questions below.
Suzie’s day / Time spent (24 hours)School / 6
Homework / 3
Babysitting / 4
Exercising / 1
Sleeping / 8
Texting / 2
A. What is the dependent variable and why?
B. What is the independent variable and why?
c. Now create a pie chart that represents the data.
· Do not forget to label ALL parts of the graph and to put a title!
Guide to Graphing
Graphing is an important procedure used by scientists to display the data that is collected during a controlled experiment. Line graphs must be constructed correctly to accurately portray the data collected. Many times the wrong construction of a graph detracts from the acceptance of an individual’s hypothesis.
A graph contains five major parts: The title, the independent variable, the dependent variable, the scales for each variable, and a legend.
The title: depicts what the graph is about. By reading the title, the reader should get an idea about the graph. It should be a concise statement placed above the graph.
The Independent Variable: is the variable that can be controlled by the experimenter. It usually includes time (dates, minutes, hours), depth (feet, meters), temperature (Celsius). This variable is placed on the X axis (horizontal axis).
The Dependent Variable: is the variable that is directly affected by the independent variable. It is the result of what happens because of the independent variable. Example: How many oxygen bubbles are produced by a plant located five meters below the surface of the water? The oxygen bubbles are dependent on the depth of the water. This variable is placed on the Y-axis or vertical axis.
The Scales for each Variable: In constructing a graph one needs to know where to plot the points representing the data. In order to do this a scale must be employed to include all the data points. This must also take up a conservative amount of space. It is not suggested to have a run on scale making the graph too hard to manage. The scales should start with 0 and climb based on intervals such as: multiples of 2, 5, 10, 20, 25, 50, or 100. The scale of numbers will be dictated by your data values.
The Legend: a short descriptive narrative concerning the graph's data. It should be short and concise and placed under the graph.
Aesthetics: Your graphs should always be neat, presentable, and easy to read. They should also take up more than half of the graph paper provided to you.
DIRECTIONS: Answer the following question now that you have read GUIDE TO GRAPHING (on the other side and completed your graphs.
1. This is the variable that is controlled by the person doing the experiment.
2. This is the key to what the graph means. It is a short, concise narrative about the data.
3. This is the variable that is directly affected by the independent variable. The result of what happens because of the independent variable.
4. This is what the graph is all about.
5. How much space should a graph take up on a single piece of paper?
6. Why do scientists use graphs?
7. How do you figure out the scale of your graph?
8. This variable is placed on the X axis.
9. This variable is placed on the Y axis.
10. List the five major parts of a graph below.