1. I DENTIFYING AND W RITING P ROPORTIONS Objective: Learn to find equivalent ratios and identify proportions.

2. R ATIO R ECAP A ratio is a comparison of two quantities(numbers) using division Three Ways to Write a Ratio FractionWith “to”With “:”

3. T RY T HIS ! What is the ratio of shaded squares to unshaded squares? box 1 box 2 These 2 ratios are called equivalent ratios GCF of 20 and 28

4. E QUIVALENT R ATIOS What are Equivalent Ratios? Equivalent ratios are ratios that make the same comparison Examples: Multiply by any number These equivalent ratios are proportional.

5. P ROPORTIONAL What is a Proportional or in Proportion? Proportions are equivalent ratios that are identical when in simplest form. Examples:

6. T RY T HIS ! Determine whether the ratios are proportional. A.. B.. Already reduced Simplify

7. T RY T HESE ! Divide both the numerator and the denominator by a common factor Multiply both the numerator and the denominator by any number Write the proportion

8. E XAMPLE 1: Determine whether the ratios are proportional.

9. E XAMPLE 2: Directions for making 12 servings of rice call for 3 cups of rice and 6 cups of water. For 40 servings it calls for 10 cups of rice and 19 cups of water. Are the ratios of rice to water proportional for both servings of rice.

10. E XAMPLE 3: Find an equivalent ratio. Then write the proportion.