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Year 5 Maths — Adding and subtracting decimals

Add and subtract numbers with tenths and hundredths by keeping the columns lined up.

Name: ________________________

Before you start

This line runs from 0 to 1. The numbered ticks are tenths, and the plain ticks between them fall halfway again. Look at how far apart 0.05 and 0.5 really are.

0.000.100.200.300.400.500.600.700.800.901.00

Ten hundredths make one tenth. That is why 0.5 is far bigger than 0.05, even though both are written with a 5.

  1. 1.4.6 + 2.35 = ?

  2. 2.2.5 + 1.3 = ?

  3. 3.Match each subtraction to its answer.

    • 1 - 0.4
    • 1 - 0.25
    • 1 - 0.05
    • 1 - 0.9
    • 1 - 0.5
    • 0.1
    • 0.5
    • 0.95
    • 0.6
    • 0.75

  4. 4.5.8 - 2.3 = ?

  5. 5.7.2 - 3.45 = ?

  6. 6.6 - 0.4 = ?

  7. 7.One jug holds 1.5 litres and another holds 0.75 litres. How much do they hold together, in litres? Give just the number.

  8. 8.Work each one out, then put them in order, smallest answer first.

    • 1.2 + 0.3
    • 2.5 - 0.4
    • 3.6 - 0.7
    • 1.9 + 0.5

Answer key — Year 5 Maths — Adding and subtracting decimals

  1. 1. 6.95
  2. 2. 3.8
  3. 3. 1 - 0.4 → 0.6; 1 - 0.25 → 0.75; 1 - 0.05 → 0.95; 1 - 0.9 → 0.1; 1 - 0.5 → 0.5
  4. 4. 3.5
  5. 5. 3.75
  6. 6. 5.6
  7. 7. 2.25
  8. 8. 1. 1.2 + 0.3 2. 2.5 - 0.4 3. 1.9 + 0.5 4. 3.6 - 0.7