Unit 2. Day 8.

4th, 5th, 6th Grade

Example A: Add or subtract. Write in simplest form. 3 8 + 1 8 4 8 1 2 3+1 2∙2 = = = = 8 8 2∙2∙2 4 8 2 2 2 4 2 2

Why don’t we add the denominators? 4 8 3 8 + 1 8 4 16

5 9 − 2 9 2 7 + 3 7 Add or subtract. Write in simplest form. Example B*: 2 7 + 3 7 Example C*:

Example B*: Add or subtract. Write in simplest form. 5 9 − 2 9 3 9 5−2 1 3 3 = = = = 9 9 3∙3 3 9 − − 3 3

Example C*: Add or subtract. Write in simplest form. 2 7 + 3 7 5 7 2+3 = = 7 7

7th Grade

Example D: Add or subtract. Write in simplest form. 23 24 − 39 24 −16 24 23−39 − 2 3 − 2∙2∙2∙2 = = = = 24 24 2∙2∙2∙3 24 16 4 6 4 4 2 2 3 2 2 2 2 2

5 32 − 33 32 − 11 16 − 1 16 Add or subtract. Write in simplest form. Example E*: − 11 16 − 1 16 Example F*: − 17 12 − −7 12 Example G*:

Example E*: Add or subtract. Write in simplest form. 5 32 − 33 32 5−33 −28 32 − 7 8 −2∙2∙7 = = = = 32 32 2∙2∙2∙2∙2 32 28 4 8 4 7 2 4 2 2 2 2 2 2

Example F*: Add or subtract. Write in simplest form. − 11 16 − 1 16 −12 16 −11−1 − 3 4 −2∙2∙3 = = = = 16 16 2∙2∙2∙2 12 16 4 4 3 4 2 2 2 2 2 2

Example G*: Add or subtract. Write in simplest form. + − 17 12 − − 7 12 − 17 12 − −7 12 −10 12 − 5 6 −17+7 −2∙5 = = = = 12 12 2∙2∙3 12 10 3 4 2 5 2 2

10 6 3 2 5 2 Example H: Add or subtract. Write in simplest form. 5 1 6 −6 5 6 31 6 41 6 − 31−41 −10 6 −2∙5 − 5 3 = = = = 2∙3 6 6 −1 2 3 = 10 6 2 5 2 3

Example I*: Add or subtract. Write in simplest form. 3 17 24 −6 5 24 89 24 149 24 − − 5 2 89−149 −60 24 −2∙2∙3∙5 = = = = 2∙2∙2∙3 24 24 −2 1 2 = 24 60 4 6 4 15 2 3 2 3 5 2 2 2