1. LESSON 4 INTRODUCING SCALE FACTOR

2. OBJECTIVES Content Objective: Make comparisons and reason about ratio and proportional situations using proportions. Language Objective Create proportions with equivalent ratios by enlarging and shrinking objects using scale factor.

3. ACE OF CAKES STARS DO MATH What is a ratio? What is the difference between a ratio and a proportion? How do you determine is two ratios are proportional?

4. COLORED TILE RATIOS Using the colored tiles create the ratio Red : Green tiles Be ready to share your ratio.

5. COLORED TILE RATIOS Using the colored tiles create the ratio Red : Green tiles Are any of the ratios the same? Be ready to share your ratio.

6. COLORED TILE RATIOS Using the colored tiles create the ratio Red : Green tiles Are any of the ratios the same? Be ready to share your ratio.Create an equivalent ratio to Group B.

7. COLORED TILE RATIOS Using the colored tiles create the ratio Red : Green tiles Are any of the ratios the same? Be ready to share your ratio.Create an equivalent ratio to Group B. How did you know this ratio was equivalent?

8. PROPORTIONS If one quantity in a ratio is multiplied or divided by a factor, then the other quantity must be multiplied by the same factor to maintain a proportional relationship. A proportion is a relationship of equality between two ratios.

9. VERONICA WAS THE WINNER OF THE BEST TASTING CAKE. AS A REWARD, DUFF HAS HIS TEAM HAVE DECIDED TO RECREATE HER CAKE FOR ALL 6 TH GRADE CLASSES. What do observe in the cake pictures?

10. VERONICA WAS THE WINNER OF THE BEST TASTING CAKE. AS A REWARD, DUFF HAS HIS TEAM HAVE DECIDED TO RECREATE HER CAKE FOR ALL 6 TH GRADE CLASSES. Suppose Duff plans to double the size of the cake. This means he has to multiply everything by _________. To double something means to use a scale factor of _________

11. VERONICA WAS THE WINNER OF THE BEST TASTING CAKE. AS A REWARD, DUFF HAS HIS TEAM HAVE DECIDED TO RECREATE HER CAKE FOR ALL 6 TH GRADE CLASSES. Duff decides that will not be enough cake. Instead he will make it three times as big. This means he has to multiply everything by _________.. To triple something means to use a scale factor of _________

12. VERONICA WAS THE WINNER OF THE BEST TASTING CAKE. AS A REWARD, DUFF HAS HIS TEAM HAVE DECIDED TO RECREATE HER CAKE FOR ALL 6 TH GRADE CLASSES. Duff also plans to triple the amount of strawberry and blackberry toppings of the original cake.

13. VERONICA WAS THE WINNER OF THE BEST TASTING CAKE. AS A REWARD, DUFF HAS HIS TEAM HAVE DECIDED TO RECREATE HER CAKE FOR ALL 6 TH GRADE CLASSES. Duff plans to triple the amount of strawberry and blackberry toppings of the original cake.

14. SCALE FACTOR Come up with a definition of scale factor at your table.

15. GUIDED PRACTICE We will work through question 1 & 2 together. There are many ways to create proportions. Finding equivalent ratios Tape diagrams Cross products-f or two ratios to form a proportion their cross products must be equal. This is called solving proportions.

16. INDEPENDENT WORK Preparing for New York

17. LET’S REVIEW TOGETHER

18. REVIEW: How do you know if two ratios are equivalent? Is one method of determining proportionality better than other methods?

19. MIX-FREEZE-PAIR We will be asking questions about proportions and scale factor. Each person will have time to think. We will select either #1 or #2 to explain what they think the answer is and why to their partner. Mingle around the room until I call “Freeze”. Choose the person closest to you to be your partner. Decide which partner is #1 and which will be #2.

20. If I want to double a recipe, I would multiply by a Scale Factor of _________ because _______________________________

21. If I am selling Girl Scout Cookies and I want to earn four times what they cost me, I must use a scale factor of _______________ because ____________________________

22. If I have a proportion 12:15 = 4:5, then the scale factor is ______________________ because _______________________

23. Are these ratios proportional? If so what is the scale factor? If not, why not?

24. Are these ratios proportional? If so what is the scale factor? If not, why not?

25. Do these ratios form a proportion? If so what is the scale factor? If not, why not?

26. Do these ratios form a proportion? If so what is the scale factor? If not, why not?

27. PROPORTION NOTES AND PRACTICE

28. SOLVING PROPORTIONS