1. + Proportional Relationships By Janie Solinski-Ruddy for use with Chirping Crickets

2. + Proportions are Comparisons of Two Equal Ratios A relationship where one number of the ratio increases by the same factor as the other number in a ratio is said to be DIRECTLY PROPORTIONAL A relationship where one number of the ratio decreases by the same factor as the other number in a ratio increases is said to be INVERSLY PROPORTIONAL.

3. + Directly Proportional Relationships Number of calories in a candy bar as the number of sugar grams increases. The hours of studying and grade on a test. The number of hours that the lights are on in a home and the cost of the electric bill. Provide Your Own Example! Evan Amos http://en.wikipedia.org/wiki/Reese's_Fas t_Break#mediaviewer/File:Candy- Reeses-Fast-Break-Broken.jpg http://www.public-domain- image.com/objects-public-domain- images-pictures/electronics-devices- public-domain-images- pictures/electric-lights-pictures/light- bulb.jpg.html

4. + Inversely Proportional Relationships The hours spent exercising and Body Mass Index The faster you drive the fewer hours it takes to get to your destination The more people who help paint a fence, the number of hours needed to paint the fence by each person decreases. Provide an Example of your own! Borden 31 http://commons.wikimedia.org/wiki/File:Painting_ a_Fence.JPG Senior Airman Myles Stepp http://www.altus.af.mil/shared/media/photodb/ photos/111021-F-BT139-620.jpg

5. + Can a Directly Proportional Relationship be Represented Graphically? Create a graph that you think will show a directly proportional relationship. Does your graph look similar? A directly proportional relationship will form, usually, an increasing line. Sewaqu http://en.wikipedia.org/wiki/Least_squares#mediaviewer/File:Linea r_regression.svg

6. + Can an Inversely Proportional Relationship be Represented Graphically? Create a graph that you think will show an inversely proportional relationship. Does your graph look similar? Renze, John and Weisstein, Eric W. "Scatter Diagram." From MathWorld--A Wolfram Web Resource. http://mathworld.wolfram.com/ScatterDiagram.html