Source: https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-7-method-g-partial-differences-method

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# Method G - Partial Differences Method

CPD for Primary: Subtraction Methods for KS2 Maths (by Jo Morgan), topic 2.1.7

## Partial Differences Method: 753 − 491

### Step 1

![Step 1](https://image-v2.cdn.app.senecalearning.com/2020-04/ef59fe94-1d7e-4e9b-8f9e-f8638377a138/Method%20G%20-%20Example%201%20(5).png)

- Write out the subtrahend under the minuend, lining up the digits so that the hundreds, tens and ones digits of each number are in the same columns respectively.

### Step 2

![Step 2](https://image-v2.cdn.app.senecalearning.com/2020-04/af71988a-0080-4bcc-8d58-0eecbcea2caf/Method%20G%20-%20Example%201%20(12).png)

- We could work from either right to left or left to right here.
- Starting from the right, we subtract 1 from 3 and write the difference in the ones column. 3 − 1 = 2.

### Step 3

![Step 3](https://image-v2.cdn.app.senecalearning.com/2020-04/b48aca6a-4731-4714-8b34-73c58b784702/Method%20G%20-%20Example%201%20(11).png)

- Subtract 9 from 5 and write the difference in the tens column. 
- 5 − 9 = −4.

### Step 4

![Step 4](https://image-v2.cdn.app.senecalearning.com/2020-04/fb161bc6-9486-46d4-abaa-25f5a0407190/Method%20G%20-%20Example%201%20(9).png)

- Unlike in other methods, it’s fine to write a negative number in the bottom row.
- Subtract 4 from 7 and write the difference in the hundreds column. 
- 7 − 4 = 3.

### Step 5

![Step 5](https://image-v2.cdn.app.senecalearning.com/2020-04/34f628df-1246-4f76-b0fa-7fb5bbe27389/Method%20G%20-%20Example%201%20(13).png)

- Now calculate the value of the difference. 
- Reading off the bottom row, we have 300 − 40 + 2. 
- 300 − 40 + 2 = 262
 - So 753 − 491 = 262

## Test yourself on Method G - Partial Differences Method

- Which way do we work when using the Partial Difference Method?
- **Example question: Use the Partial Difference Method to calculate 832 − 376.**What shouls students write in the hundreds, tens and ones column?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/eab4f483-2118-4224-8daa-b5f64232f209/section/882108e7-7d73-4356-b160-ec18ef8a4803/session)

- Previous topic: [2.1.6 Method F - Constant Difference Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-6-method-f-constant-difference-method.md)
- Next topic: [2.1.8 Method H - Complementary Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-8-method-h-complementary-method.md)

## CPD for Primary: Subtraction Methods for KS2 Maths (by Jo Morgan) contents

### 1 Course Overview
- 1.1 Course Structure & Commonly Asked Questions
  - [1.1.1 Introduction to the Course & Common Questions](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/1-1-1-introduction-to-the-course-and-common-questions.md)

### 2 Subtraction Methods
- 2.1 Subtraction Methods
  - [2.1.1 Method A - Decomposition Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-1-method-a-decomposition-method.md)
  - [2.1.2 Method B - Equal Addition Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-2-method-b-equal-addition-method.md)
  - [2.1.3 Method C - Expanded Form Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-3-method-c-expanded-form-method.md)
  - [2.1.4 Method D - Partitioning Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-4-method-d-partitioning-method.md)
  - [2.1.5 Method E - Counting-Up Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-5-method-e-counting-up-method.md)
  - [2.1.6 Method F - Constant Difference Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-6-method-f-constant-difference-method.md)
  - [2.1.7 Method G - Partial Differences Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-7-method-g-partial-differences-method.md)
  - [2.1.8 Method H - Complementary Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-8-method-h-complementary-method.md)
  - [2.1.9 Method I - Nines Complement Method](https://senecalearning.com/en-gb/revision-notes/teacher-cpd/cpd-for-primary-subtraction-methods-for-ks2-maths-seneca-certified/2-1-9-method-i-nines-complement-method.md)