2.1.3
Method C - Expanded Form Method
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Expanded Form Method: 753 − 491
This method is identical to the Decomposition Method (Method A) except we show the decomposition much more clearly.
,h_400,q_80,w_640.png)
Step 1
- Write out the subtrahend and the minuend as a sum of their hundreds, tens and ones.
,h_400,q_80,w_640.png)
Step 2
- Now set them out in columns.
,h_400,q_80,w_640.png)
Step 3
- Start at the right. Subtract 1 from 3.
- Write the difference at the bottom, in the ones column.
,h_400,q_80,w_640.png)
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.
,h_400,q_80,w_640.png)
Step 5
- Now we can subtract 90 from 150.
,h_400,q_80,w_640.png)
Step 6
- And subtract 400 from 600.
Step 7
- The difference is the sum of the numbers in the bottom row.
- 200 + 60 + 2 = 262.
1Course Overview
1.1Course Structure & Commonly Asked Questions
2Subtraction Methods
2.1Subtraction Methods
2.1.1Method A - Decomposition Method2.1.2Method B - Equal Addition Method2.1.3Method C - Expanded Form Method2.1.4Method D - Partitioning Method2.1.5Method E - Counting-Up Method2.1.6Method F - Constant Difference Method2.1.7Method G - Partial Differences Method2.1.8Method H - Complementary Method2.1.9Method I - Nines Complement Method
Jump to other topics
1Course Overview
1.1Course Structure & Commonly Asked Questions
2Subtraction Methods
2.1Subtraction Methods
2.1.1Method A - Decomposition Method2.1.2Method B - Equal Addition Method2.1.3Method C - Expanded Form Method2.1.4Method D - Partitioning Method2.1.5Method E - Counting-Up Method2.1.6Method F - Constant Difference Method2.1.7Method G - Partial Differences Method2.1.8Method H - Complementary Method2.1.9Method I - Nines Complement Method
Practice questions on Method C - Expanded Form Method
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- 1Which part of this student's working is incorrect?Multiple choice
- 2Has the student gone wrong? If so, where?Multiple choice
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