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Here we will learn about **adding decimals** including how to solve problems that involve decimal addition.

There are also adding decimals worksheets with word problems and problem solving questions based on Edexcel, AQA and OCR exam questions, along with further guidance on where to go next if you’re still stuck.

**Adding decimals **involves using column addition to add together decimal numbers by lining up the digits so that they have the same place value.

The ones, decimal points, tenths, hundredths etc. should be lined up. This is particularly important to do if the values we are adding have been given to a different number of decimal places.

E.g.

A similar approach will be used for decimal subtraction.

In order to add decimals:

**Set up a column addition, writing one number above the other. Make sure the decimal points line up to ensure numbers in each column have the correct place value.****Add each column from right to left remembering to carry numbers to the next column when you get a two digit number.****Read off your answer, remembering to include the decimal point.**

Get your free adding decimals worksheet of 20+ questions and answers. Includes reasoning and applied questions.

DOWNLOAD FREEGet your free adding decimals worksheet of 20+ questions and answers. Includes reasoning and applied questions.

DOWNLOAD FREE**Adding decimals** is part of our series of lessons to support revision on **decimals**. You may find it helpful to start with the main decimals lesson for a summary of what to expect, or use the step by step guides below for further detail on individual topics. Other lessons in this series include:

Add together

**Set up a column addition, writing one number above the other. Make sure the decimal points line up to ensure numbers in each column have the correct place value.**

2**Add each column from right to left remembering to carry numbers to the next column when you get a two digit number.**

3**Read off your answer, remembering to include the decimal point.**

The answer is

Find the sum of

**Read off your answer, remembering to include the decimal point.**

The answer is

Work out

**Read off your answer, remembering to include the decimal point.**

The answer is

Add together £

Fill in missing zeros if it helps.

**Read off your answer, remembering to include the decimal point.**

The answer is £

Find the sum of

Fill in missing zeros if it helps.

**Read off your answer, remembering to include the decimal point.**

The answer is

Work out

Fill in missing zeros if it helps.

**Read off your answer, remembering to include the decimal point.**

The answer is

**Not lining up the decimal point**

A common error when adding decimals occurs when the decimal points are not lined up but instead the last digits are lined up.

E.g.

1. Add together 3.7 and 5.6

9.3

8.13

8.3

9.13

You must remember to line up the decimal points carefully and carry to the next column if the sum of the digits gives a two digit answer.

2. Work out £12.84 + £6.19

£18.103

£19.03

£18.913

£19.3

3. Find the sum of 0.069 and 5.987

5.1056

6.677

6.56

6.056

4. Add together 2 and 3.87

5.87

3.89

4.07

23.87

You must remember to line up the decimal points carefully, you can fill in missing zeros if it helps.

5. Find the sum of 9.04 and 17.381

26.421

18.285

107.781

26.385

You must remember to line up the decimal points carefully and carry to the next column if the sum of the digits gives a two digit answer. You can fill in missing zeros if it helps.

6. Work out 20.3 + 13.67 + 0.998

2568

4.395

34.968

34.068

1.

(a) Work out £ 13.67 + £ 8.59

(b) Work out 55.6 + 2.392 + 12.48

**(3 marks)**

Show answer

a)

Correct answer of £ 22.26

**(1)**

b)

57.992 or 68.08 or 14.872 seen

**(1)**

Correct answer of 70.472

**(1)**

2. Complete the following calculations

(a)

(b)

**(5 marks)**

Show answer

a)

2 in first box

**(1)**

7 in second box

**(1)**

b)

8 in top box

**(1)**

1 in first box in second row

**(1)**

6 in second box in second row

**(1)**

3. Find the perimeter of the irregular pentagon.

**(2 marks)**

Show answer

4.1+3.5+2.9+4.6+3.8

**(1)**

Correct answer of 18.9

**(1)**

You have now learned how to:

- Understand and use place value for decimals, measures and integers of any size
- Use the four operations, including formal written methods, applied to integers, decimals, proper and improper fractions, and mixed numbers, all both positive and negative

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