1 Answer

Line graphs are used to display data or information that changes continuously over time. Line graphs allow us to see overall trends such as an increase or decrease in data over time. 

Bar graphs are used to compare facts. The bars provide a visual display for comparing quantities in different categories or groups.<font face="Arial, Helvetica, sans-serif"> </font>Bar graphs help us to see relationships quickly. 

Circle Graphs are used to compare the parts of a whole. Circle graphs represent data visually in the same proportion as the numerical data in a table: The area of each sector in a circle graph is in the same proportion to the whole circle as each item is to the total value in the table. 

I think the circle graph is better for comparison. http://www.mathgoodies.com/lessons/graphs/compare_graphs.html