1. Ratios & Rates of Change Chapter 11, Section 2, 3, 4

2. Ratio A ratio is a comparison of like or unlike quantities. It can compare a part to a part, a part to a whole, or the whole to a part. Does this sound like something else we have studied about? A FRACTION This can be written as a fraction (3/9) or 3 to 9 or 3:9.

3. Practice Let’s write a ratio of the number of people with blond hair to the number of people with black hair. Boys to girls Basketball players to non basketball players

4. Equal Ratios We can find equal ratios that show the same comparison. For the ratio 18:24 18 24

5. Rates A rate is a ratio that compares unlike units. A common rate is miles per hour. If the comparison is to one unit, it is called a unit rate. Example: Give the unit rate for 22 laps in 5 minutes. 22 laps = laps 5 minutes 1 minute

6. Practice Write each rate as a unit rate. 15 books in 3 weeks 8 visits in 5 days

7. Constant or Vary What does constant mean? What does vary mean? Constant-to stay the same Vary-to change