How to visualise multiplication with an array

The array method is a way of calculating multiplication with large numbers.
It is set out by splitting each number in the calculation in to tens and ones.

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Learn how to use an array to visualise multiplication

Setting up the array

The array method only works when one of the numbers being multiplied is bigger than 10.

Look at both numbers and, where necessary, split into tens and ones.

Draw out a rectangle. Label the top of the rectangle with one of the numbers you have split in to tens and ones and the height of the rectangle with the other.

Have a go

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STEP 1 - To work out how many players there are in total, first split the number of players on each team into 10 and 5 (tens and ones). This will make the multiplication easier.
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STEP 2 - There are 7 teams. Write 7 on the left hand side.
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STEP 3 - Draw a grid of rectangles – one to represent 7 x 10, and one to represent 7 x 5.
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STEP 4 - Calculate 7 x 10 = 70 and 7 x 5 = 35. If you add these together you’ll get 105, the total number of players!

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Setting up the array

Have a go

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More on Operations/calculations