Conversions

1. Conversions

2. Your first conversion!! Convert your age in years to seconds.

3. In science, it is often useful to be able to convert from one unit of measure to another For example: If you have 24 students in a class and you want to give each student 4 cookies, how many dozen do you need?

4. First we will see how it works withdozen.

5. You know that a dozen is 12 of something. If you have 36 donuts, how many dozen donuts do you have?

6. Use this relationship to convert from individual donuts to dozen donuts: You want to know how many dozen in 36 donuts, and you know there is 1 dozen per 12 donuts, or 1 dozen 12 donuts

7. 1 dozen 12 donuts 36 donuts x In the problem how many dozen in 36 donuts, you know there is 1 dozen per 12 donuts, or 1 dozen Use this relationship to convert from individual donuts to dozen donuts: 12 donuts

8. In the problem how many dozen in 36 donuts, you know there is 1 dozen per 12 donuts, or 1 dozen Use this relationship to convert from individual donuts to dozen donuts: 12 donuts 1 dozen 12 donuts 36 donuts x 1 dozen 12 donuts 36 donuts x =

9. 36 dozen 12 = In the problem how many dozen in 36 donuts, you know there is 1 dozen per 12 donuts, or 1 dozen Use this relationship to convert from individual donuts to dozen donuts: 12 donuts 1 dozen 12 donuts 36 donuts x 1 dozen 12 donuts 36 donuts x =

10. 36 dozen 12 = 3 dozen = In the problem how many dozen in 36 donuts, you know there is 1 dozen per 12 donuts, or 1 dozen Use this relationship to convert from individual donuts to dozen donuts: 12 donuts 1 dozen 12 donuts 36 donuts x 1 dozen 12 donuts 36 donuts x =

11. 36 dozen 12 = 3 dozen = In the problem how many dozen in 36 donuts, you know there is 1 dozen per 12 donuts, or 1 dozen Use this relationship to convert from individual donuts to dozen donuts: 12 donuts 1 dozen 12 donuts 36 donuts x 1 dozen 12 donuts 36 donuts x =

12. 3 dozen = 36 donuts

13. there are 12 donuts in 1 dozen 12 donuts 2.5 dozen x 1 dozen If you have 2.5 dozen donuts, how many individual donuts are there?

14. 2.5 dozen x 12 donuts 1 dozen 2.5 x 12 donuts = 1 30 donuts = If you have 2.5 dozen donuts, how many individual donuts are there? 12 donuts 2.5 dozen x = 1 dozen

15. notice the two conversion factors are reciprocals of each other Here are the two problems side by side: 2

16. = 1 = 1 12 donuts 1 dozen 1 dozen 12 donuts 12 donuts = 1 dozen

17. converts donuts to dozen 12 donuts 1 dozen 1 dozen 12 donuts 12 donuts = 1 dozen = 1 = 1

18. converts dozen to donuts 12 donuts 1 dozen 1 dozen 12 donuts 12 donuts = 1 dozen = 1 = 1

19. Since conversion factors always equal 1, you can multiply them by anything you want and still end up with the same thing except that it will be in a different form. !!!REMEMBER!!! You are changing the form of the number not the value.

20. Let’s try converting donut mass to number of donuts…

21. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams?

22. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? What’s the conversion?

23. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? 1. what is the question asking you to convert?

24. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? 1. what is the question asking you to convert? grams to donuts

25. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? 2. what is the relationship between grams and donuts?

26. If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? 2. what is the relationship between grams and donuts? 150 grams = 1 donut

27. 3. set up the conversion factors:

28. 150 g 1 donut = 1 1 donut 150 g = 1 150 g = 1 donut so… and

29. 150 g 1 donut = 1 1 donut 150 g = 1 150 g = 1 donut these are your conversion factors

30. 150 g 1 donut = 1 1 donut 150 g = 1 150 g = 1 donut converts donuts to grams (grams on top)

31. 150 g 1 donut = 1 1 donut 150 g = 1 150 g = 1 donut converts grams to donuts (donuts on top)

32. The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams?

33. begin with the amount given in the problem The question is… 9900 grams If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams?

34. The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams?

35. The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? each donut has a mass of 150 grams

36. converts grams to donuts The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? each donut has a mass of 150 grams

37. The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams?

38. The question is… If you have 9900 grams of donuts, how many donuts do you have if each donut has a mass of 150 grams? how many donuts do you have

39. =

40. What if it’s not donuts? • You have to know the relationship!!

41. English • 1ft. = 12in • 3ft. = 1 yd • 5280ft. = 1mile • What are the conversion factors?

42. Metric Relationships • King Henry Died By Drinking Chocolate Milk

43. Common conversions • 2.54 cm = 1 in 4 qt = 1 gallon • 5280 ft = 1 mile 4 cups = 48 tsp • 2000 lb = 1 ton • 1 kg = 2.205 lb • 1 lb = 453.6 g • 1 lb = 16 oz • 1 L = 1.06 qt

44. Now for some practice!!!