1. Reading Graphs Objective: 1. Learn to read numbers from different types of graphs. 2. Learn to compare numbers within the same graph.

2. Graphs are a useful way to organize information.  In this lesson we will review 4 types of graphs:  Bar Graphs  Pictographs  Line Graphs  Circle Graphs

3. Bar Graphs  A bar graph uses vertical or horizontal bars to display numerical information. The length of the bar tells you the number it represents.

4. Pictograph  A pictograph uses symbols to represent data.  All of the symbols have the same value.  To determine the measure of an item in a pictograph, count the number of symbols and multiply them by the value of the symbol. Answer the following questions using the pictograph above: 1.How much was the production of apples in 2004? 2.What is happening to the production of apples between the year 2004 to 2008?

5. Line Graph  A line graph is used to show how a set of data changes over a period of time.  Each point represents an item of the data.  The height of the point represents the value of the data.  The time is shown by how far to the right the point is.  By observing the upward or downward slant of the lines connecting the points, you can describe the trends in the data. Questions: 1.What is the line graph about? 2.What is the busiest time of day at the store?

6. Circle Graph Questions: 1.What percentage of students prefer pepperoni pizza? 2.Which is the least favorite pizza topping?  A Circle Graph is made by dividing a circle into sections or categories. It allows for comparison of the part to the whole.  The larger the value of the data, the wider the section that represents the value.

7. Homework:  Fill in the blank with the name of the graph described. 1. A ____________ uses symbols to represent data. 2. A _____________ is used to show how a set of data changes over a period of time. 3. A _____________, is made by dividing a circle into sections. 4. A _____________ uses bars to display numerical information.  Use the line graph at the right to answer each question. 5. At what age do teens have the greatest number cell phones? __________ 6. At what age do teens have the least number of cell phones? ____________ 7. How many cell phones do 15 year-olds have? _________