Multiplying large numbers by splitting

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Multiplying large numbers by splitting

• Created by Sabrina Edmondson
• Adapted from BBC online

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Multiplying large numbers by splitting

• Have a look at the following equation
• 255 x 5

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Multiplying large numbers by splitting

• First split the number into hundreds, tens and
  ones.
• 255 splits into 200, 50 and 5

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Multiplying large numbers by splitting

• Then, multiply each of the numbers by 5.5 x
  200 1 0005 x 50 2505 x 5 25

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Multiplying large numbers by splitting

• This method can be represented in a grid, as
  shown below.

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Multiplying large numbers by splitting

• Finally, add the three numbers together to get
  your answer.

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Multiplying large numbers by splitting

• So 255 x 5 1,275
• Remember check the answer by doing the
  opposite! 1,275 5 255

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Multiplying large numbers by splitting

• Now have a look at this equation
• 255 x 25

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Multiplying large numbers by splitting

• First split the number into hundreds, tens and
  ones.
• 255 splits into 200, 50 and 5 (these go along
  the top)
• 25 splits into 20 and 5 (these go along the
  sides)

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Multiplying large numbers by splitting

• Then, multiply each number in the column by each
  number in the row.
• Have a look at the grid below.

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Multiplying large numbers by splitting

• Add up each column, then add the resulting
  numbers together.

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Multiplying large numbers by splitting

• So 255 x 25 6,375
• Remember check the answer by doing the
  opposite! 6,375 25 255