This document discusses addition and subtraction of sets. It explains that addition is putting sets together to find the total number of objects. Subtraction is taking away objects from a set to determine how many are left. The author is Allison Staley, a student at Grand Valley State University studying mathematics education. Resources on the topics of addition and subtraction are provided.

1. HOW ADDITION AND SUBTRACTION WORK Allison Staley ED 205-06

3. ADDITION: First, look at the two sets: Set A Set B Count how many triangles are in each set. Click here to see the answers! Quit

7. ADDITION & SUBTRACTION Quit

10. CONCEPT MAP: Quit

11. Set A Set B There are 2 There are 3 Quit Return

12. It will give us 5. So 2 + 3 = 5 Quit Return

13. There are 5 triangles. Quit Return

14. There are 3 triangles left. So 5 – 2 = 3 Quit Return