How do you subtract with fractions or mixed numbers by decomposing?

1. How do you subtract with fractions or mixed numbers by decomposing? 3 - = 2 - 3 - 1

2. In this lesson you will learn how to subtract with fractions or mixed numbers by decomposing.

3. How do I decide which equivalent fraction to use? This could go on forever! We know that equivalent fractions show equal amounts. = = = = =

4. The possibilities are endless! Whole numbers can be decomposed as fractions or mixed numbers. 4 4 5 = = 1 = = 1 2 = =

5. Mixed numbers like 1 can be decomposed into their individual parts. = + 1

6. Forgetting to decompose. 4 - 1≠ 3 4 - 1 = 2 ≠

7. I need to subtract I’ll cut just one cookie making two halves. 3 = 2 Mom says I can eat the cookies if I give my sister of a cookie. I don’t want to cut all the cookies. Think about cookies. - 2 cookies Now I have 2 + I can easily subtract .

8. This works with a fraction bar model. = 2 3 1 =- - 1 2

9. This works with mixed numbers. 2 = 1 = 2 = 1 + + I need to subtract from 2 I need to decompose into more pieces. I need to take away one half, but the minuend isn’t divided in halves. When one denominator is a divisor of the other, only one fraction has to be changed. I will use an equivalent fraction. = I will decompose one of the wholes into . = 1 = - - = 1 = 1

10. 3 - 1 I need to subtract 1 1 = 2 3 1 - 1 = - 1 I need to decompose one of the wholes into . 1

11. In this lessonyou have learned how to subtract with fractions or mixed numbersby decomposing.