2.04 Subtraction without regrouping
Are you ready?
Do you feel that you have mastered  addition problems , using some different methods?
Examples
Example 1
Find the value of 720 + 250.
We can use a number line to add numbers, by plotting the larger number then jumping to the right by the smaller number.
Subtraction with place value models and columns
Just like addition, we can use place value blocks (also called base 10 models) to solve addition. See how we do this in this video.
We can also use place value columns to solve subtraction problems working down our page. In this video we look at subtracting a number in the thousands from another number in the thousands.
Examples
Example 2
Use the number line to find the answer to 667 -637
First place 667 on the number line.
Place 637 on the number line.
Use the number line to work out the difference between 667 and 637.
When we are subtracting down the page, it's really important to start from the right (ones place) and work to the left, no matter how many digits our numbers have.
