Teaching how to add and subtract whole numbers.

1. Adding and Subtracting Whole Numbers By Angela Gusmano

2. Adding

3. First, you need to know… Associative Property of Addition When: (a + b) + c = a + (b + c) Commutative Property of Addition When: a + b= b + a Zero Property of Addition When: a + 0= a

4. 4,285+ 124 Always start with the ones.

5. Let’s Try Some! 1 1 1 4,285 + 124 4,409 2,402 +1,789 4,191

6. More Practice! 1 1 1 1 5,765 + 6,341 12,106 1,891 + 298 2,189

7. Subtraction

8. 4,987- 2,158 Always start with the ones.

9. Let’s Try Some! 2 12 17 7 4,987 - 2,158 3,230 - 320 1,910 2,829

10. More Practice! 1 12 4 12 8 10 9,222 - 6,180 5,290 - 1,488 3,802 3,042

11. Now you should be able to add and subtract whole numbers!

12. Sources http://michigan.gov/documents/MathGLCE_140486_7.pdf http://www.eduplace.com/math/mw/g_4.html