3.04 Subtraction strategies
Lesson
Are you ready?
Can you remember how we use a number line to subtract one number from another? Give this problem a try.
Use the number line to help you find the value of $46-12$46−12.
$46-12$46−12$=$=$\editable{}$
Vocabulary:
-
Another word that we can use to describe the ones place is 'units'.
Learn
We can use place value models as well as the bridge to ten strategy to help us with subtraction. Let's see how in this video.
Apply
Question 1
Use a strategy to find $44-9$44−9.
Learn
Another way to solve subtraction is to use the compensation strategy. In this video we can see just how it works.
Apply
Question 2
If $70-12=58$70−12=58, use a strategy to find $69-12$69−12.
Remember!
We can use things we already know to help us with subtraction.
- Number lines can help us see the jumps between numbers
- Bridging to $10$10 can help us get to $10$10, so that subtracting can be much quicker
- Compensation uses the answer of one problem, to find the answer to another problem