Column Method

Column Addition

We can use column addition to add numbers together that are difficult to do mentally. Column addition is a way of writing down your working.

Column addition

When adding using column addition, we need to line the numbers up in the columns which represent their place value.

Method

When you use column calculations, you need to always start by adding the smallest column.
- This is on the right of the column addition calculation.
Write the answer directly below the column as shown.

Method cont.

Then add the next column of numbers,

Answer

Continue to add the next column on the left until you have no more columns left to add.
The final answer is the number you are left with below.

Carrying

Sometimes the two digits in a column add up to make 10 or more.
- 8 + 6 = 14
So we need to carry a 1 into the column on the left.
This 1 is included when we go to add this column.
- 4 + 2 + 1 = 7

Column Subtraction

We can also use the column method to take numbers away from other numbers.

Column Subtraction

When adding using column subtraction, we line the numbers up in the columns which represent their place value.

Method

When you use column calculations, you need to always start by subtracting the smallest place value column.
- This is on the right of the column subtraction calculation.
Write the answer directly below the column as shown.

Method cont.

Then subtract the next column of numbers.

Answer

Continue to subtract the next column on the left until you have no more columns left to subtract.
The final answer is the number you are left with below.

Carrying

Sometimes the top digit in a column is less than the bottom digit.
So we need to borrow a "ten" from the column on the left as shown.
We then take away the bottom digit away from the new top digit.
We have to take away one from the digit we borrowed from.

1Year 3 - Number

2Year 3 - Measurement

2.1Length

2.1.1Length

2.1.2Comparing Lengths

2.1.3Add & Subtract Lengths

2.1.4Perimeter

2.2Mass

2.2.1Mass

2.2.2Comparing Masses

2.2.3Add & Subtract Masses

2.3Volume & Capacity

2.3.1Volume & Capacity

2.3.2Comparing Volumes

2.3.3Add & Subtract Volumes

2.4Money

2.4.1Money

2.4.2Counting Money

2.4.3Adding & Subtracting Money

2.5Time

2.5.1Units of Time

2.5.2Clocks

2.5.3Telling the Time

2.5.4Time of the Day

2.5.512-Hour & 24-Hour Clocks

2.5.6Measuring Time

3Year 3 - Geometry

3.1Angles

3.1.1Angles in Degrees

3.1.2Types of Angle

3.2Properties of Shapes

3.2.12D Shapes

3.2.23D Shapes

3.3Straight Lines

3.3.1Straight Lines

3.3.2Parallel & Perpendicular Lines

4Year 3 - Statistics

4.1Statistics

4.1.1Statistics

4.1.2Pictograms & Bar Charts

5Year 4 - Number

6Year 4 - Measurement

6.1Units

6.1.1Metric Measurements

6.1.2Adding & Subtracting Money

6.2Time

6.2.1Converting Units of Time

6.2.2Changing the 12-Hour Clock to the 24-Hour Clock

6.2.3Changing the 24-hour Clock to the 12-Hour Clock

7Year 4 - Geometry

7.1Properties of Shapes

7.1.1Symmetry

7.1.2Types of Triangle

7.1.3Quadrilaterals

7.2Perimeter & Area

7.2.1Perimeter

7.2.2Area

7.3Position & Direction

7.3.1Coordinates

7.3.2Translation

8Year 4 - Statistics

8.1Statistics

8.1.1Types of Data

8.1.2Pictograms & Bar Charts

8.1.3Line Graphs

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