Same & Different: Which Number Is Missing?
Look at the two pictures. What do you notice?
- How are pictures A and B mathematically the same, and how are they different?
- A and B are the same because …
- A and B are different because …
- Think of an equation using 60, 85, and 145. Choose one number for the unknown. Make a third picture to represent your equation. Explain how your picture is the same as pictures A and B, and how it is different.
Google doc for printing and copying
Reference for Educators
Sample problems and solutions