Graphing Review NOTES * Composition Book

Why construct a graph? Graphs are pictures of information or data. It’s faster and easier to interpret data by looking at a picture. Graphs organize data! Graphs require correct “ingredients” or components to be readable and understandable!

3 types: 1)Bar 2)Line 3)Pie/ Circle

Bar and Line graphs X – axis  Horizontal  Represents the independent variable Independent variable – variable that is chosen by the experimenter Y- axis  Vertical  Represents the dependent variable Dependent variable – determined by the independent variable

When to use… Bar Comparing data quickly and easily Example: *Grades in a class *Growth of plants Line Changes over time Example: *Number of bathing suits sold each month of the year *Change in your height throughout 7 th grade

Pie Graphs Used for showing percentages Example: *Percentage of students picking various lunch entrees *Percentage of your allowance that will go toward various purchases Data must be able to be converted to percentages Circle shaped The full “pie” is equal to 100 percent. Independent variable – whatever the pie or slice represents Dependent variable – size of the pie slice (the %)

ALL graphs Must have 3 things (the ingredients): An appropriate SCALE A TITLE X and Y-axis LABELED (bar and line only) Think: S, T, L!