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Watch: Multiplying in your head

When multiplying by 10 in our heads, we can move each number a place value column to the left and add a zero.

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Example 1

What is 6 x 40?

  • 6 x 40 is equal to 6 x 4 x 10
  • 6 x 4 is equal to 6 x 2 x 2
  • 6 x 2 x 2 = 24
  • 24 x 10 = 240
  • This means 6 x 40 = 240

Break down the calculation as much as you need to. If you know 6 x 4 = 24, you don't have to break it down into 6 x 2 x 2.

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Example 2

What is 0.2 x 10 ?

We move each number a place value to the left and add a zero at the end.

0.2 x 10 = 2

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Activity

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Play our fun maths game Guardians: Defenders of Mathematica. game

Use your times tables and more maths skills to defeat monsters and reclaim the Kingdom of Mathematica

Play our fun maths game Guardians: Defenders of Mathematica
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More on Multiplying and dividing

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