1. Subtraction by counting on
Key Words
Subtraction = taking away

2. Lesson Aim: To know how to subtract numbers to 100 by counting on

3. How do you solve 99-45 by counting on?
99 ?

4. We count on.
Here is how…..
Think !

5. We added = 54
99-45= = = =99
add add add 9

6. starts with the number being taken away
Counting on always:
starts with the number being taken away
ends with the number that has something taken away from it
WE find the DIFFERENCE between the two numbers.
If you need more help
please ask now…..

7. Solve these by counting on
78-89=
94-56=
67-53=
88-32=