1.3.8

Long Multiplication Using Column Method

Test yourself

Multiplying by a 2 Digit Number With the Column Method

You can also use column multiplication when you multiply by a 2 digit number. The process is slightly different than multiplying by a 1 digit number. Let's look at 4,372 × 24 as an example.

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Setting up your columns

  • You set up the multiplication by lining up the digits in your numbers using place value.
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Multiply 4,372 by 4

  • The first step is to treat the calculation as you would when multiplying by a one-digit number.
    • Multiply 4,372 by 4.
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Then multiply by 20

  • Then you look at multiplying the 4,372 by 20.
    • Multiplying by 20 may seem quite scary.
    • But it's easier than you'd think!
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Add in a 0 in the 'ones'

  • In our next row, you put a 0 at the end.
    • You put a 0 because you are multiplying by a multiple of 10.
    • All the multiples of 10 end in 0.
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Multiply 4,372 by 20

  • Start by multiplying 2 'ones' by 2 'tens'
    • Put your answer in the second row.
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Multiply 7 'tens' by 2 'tens'

  • Next, multiply 7 'tens' by 2 'tens'
    • Put your answer in the second row.
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Multiply 3 'hundreds' by 2 'tens'

  • Next, multiply 3 'hundreds' by 2 'tens'
    • Put your answer in the second row.
    • Don't forget to add the 1 that was carried from the 'tens'.
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Multiply 4 'thousands' by 2 'tens'

  • Next, multiply 4 'thousands' by 2 'tens'
    • Put your answer in the second row.
  • You have calculated:
    • 4,372 × 4 = 17,488
    • 4,372 × 20 = 87,440
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Add to find you answer

  • 4,372 × 24 is the same as (4,372 × 4) ++ (4,372 × 20).
    • 4,372 × 24 = (4,372 × 4) ++ (4,372 × 20)
    • 4,372 × 24 = 17,488 ++ 87,440
    • 4,372 × 24 = 104,928

Jump to other topics

1Year 5 - Number

2Year 5 - Measurement

3Year 5 - Geometry

4Year 5 - Statistics

5Year 6 - Number

6Year 6 - Ratio & Proportion

7Year 6 - Algebra

8Year 6 - Measurement

9Year 6 - Statistics

9.1Displaying Data

9.2Averages

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