Method C - Expanded Form Method

CPD for Primary: Subtraction Methods for KS2 Maths (by Jo Morgan), topic 2.1.3

Expanded Form Method: 753 − 491

This method is identical to the Decomposition Method (Method A) except we show the decomposition much more clearly.

Step 1

Step 1

Write out the subtrahend and the minuend as a sum of their hundreds, tens and ones.

Step 2

Step 2

Now set them out in columns.

Step 3

Step 3

Start at the right. Subtract 1 from 3.
Write the difference at the bottom, in the ones column.

Step 4

Step 4

Now we want to subtract 90 from 50. To do this without using negatives, we can exchange.
Instead of writing 750 as 700 + 50, we write it as 600 + 150.

Step 5

Step 5

Now we can subtract 90 from 150.

Step 6

Step 6

And subtract 400 from 600.

Step 7

Step 7

The difference is the sum of the numbers in the bottom row.
200 + 60 + 2 = 262.

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