1. Math Pacing Ratios and Proportions Solve each equation 1.2. 3.4.

2. Ratios and Proportions

3. A ratio is a comparison of two numbers by division. The ratio of x to y can be expressed in the following ways:

4. Ratios and Proportions Ratios are often expressed in simplest form. For example, the recipe stated that for 4 servings you need 2 cups of milk. The ratio of serving to milk may be written as: 4 to 24 : 2or Written in simplest form, the ratio of servings to milk would be: 2 to 12 : 1or

5. Ratios and Proportions Suppose you wanted to double the recipe to have 8 servings. The amount of milk required would be 4 cups. The ratio of servings to milk is When this ratio is simplified, the ratio is Notice that this ratio is equal to the original ratio.

6. Ratios and Proportions An equation stating that two ratios are equal is called a proportion. So we can state that is a proportion.

7. Example 6-1a Answer:The ratios are equal. Therefore, they form a proportion. Determine whether the ratios and form a proportion. Determine Whether Ratios Form a Proportion

8. Do the ratios and form a proportion? Answer:The ratios are not equal. Therefore, they do not form a proportion. Example 6-1b Determine Whether Ratios Form a Proportion

9. Ratios and Proportions Another way to determine whether two ratios form a proportion is to use cross products. If the cross products are equal, then the ratios form a proportion. You are using the Multiplicative Property of Equality!!