Maths Library

Adding and Subtracting Decimals: Year 5 maths

Pupils practise addition and subtraction of decimal numbers using mental and columnar methods. The questions focus on correctly aligning the decimal points and managing place-value regrouping.

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What this covers

Adding and Subtracting Decimals is taught in Year 5 (age 10 to 11) as a main teaching focus. It sits in the Decimals strand.

Worked example

Calculate 14.6 - 3.85.

  1. Align the decimal points vertically, padding 14.6 to 14.60.
  2. Subtract hundredths: 0 - 5 requires regrouping from tenths, so 10 - 5 = 5.
  3. Subtract tenths: 5 - 8 requires regrouping from units, so 15 - 8 = 7.
  4. Subtract whole numbers: 13 - 3 = 10, giving 10.75.

Answer: 10.75

Difficulty scale

The sheet generator offers five difficulty settings for this topic.

  1. Adding and subtracting decimals with one decimal place and no regrouping
  2. Decimals with the same number of places (up to 2 dp) with regrouping
  3. Decimals with different numbers of places requiring trailing zero padding (e.g. 5.2 - 1.34)
  4. Subtracting decimals from whole numbers (e.g. 10 - 3.42)
  5. Multi-step word problems involving money or metric units with up to 3 decimal places

Common mistakes

  • Right-aligning numbers instead of aligning by the decimal point
  • Omitting the decimal point in the final answer or misplacing it

Curriculum links

Indicative matches to Australian Curriculum v9. Check wording and codes against the official document.

  • AC9M5N05 Order, add, and subtract decimals up to thousandths.

Sample sheet and answers

Six questions at the level's usual difficulty. Open the editor to change, add or regenerate any of them.

Adding and Subtracting Decimals

Year 5 maths

Qs
6
Marks
6
NameDateScore / 6
1.
39.3 + 52.1 =
[1]
2.
55.6 + 63.6 =
[1]
3.
119.7 − 73.1 =
[1]
4.
31.9 + 55.4 =
[1]
5.
83.5 − 59.7 =
[1]
6.
15.3 + 43.4 =
[1]

Answer key

  1. 91.4Line up the decimal points and add; 39.3 + 52.1 = 91.4
  2. 119.2Line up the decimal points and add; 55.6 + 63.6 = 119.2
  3. 46.6Line up the decimal points and subtract; 119.7 − 73.1 = 46.6
  4. 87.3Line up the decimal points and add; 31.9 + 55.4 = 87.3
  5. 23.8Line up the decimal points and subtract; 83.5 − 59.7 = 23.8
  6. 58.7Line up the decimal points and add; 15.3 + 43.4 = 58.7