1. Do Now
If Sara can jog 2/3 of a mile in 1/3 of an hour, how many miles can she jog in one hour?

2. September 27, 2013
Finding Equivalent Ratios Essential Question: How do you use cross products and division to identify proportional relationships?

3. Cross Products
Cross product of two ratios is the product of the numerator of one ratio and the denominator of the other ratio.

4. Determine if ratios form a proportion9 6 51 34
Determine if ratios form a proportion

5. Determine if ratios form a proportion12 32 20 50
Determine if ratios form a proportion

6. Cross Product Property
Remember b≠ 0 and d≠0. Why?

7. Use Division to test for Ratio Equivalency
2 =

8. Let’s Try Another Problem
2.5 = 4 5 9

9. Food: You can buy 3 medium pizzas at The Pizza Place for $18 or 5 medium pizzas for $30. Are these offers equivalent?

10. Teams: Determine if 42 people on 7 teams and 64 people on 8 teams are equivalent. Explain your reasoning.

11. Describe the two ways to finding equivalent ratios.
Cross Products
Dividing the fractions into decimals