Skillswise Factsheet
N1/L1.3
N1/L1.5

Multiplying large numbers by splitting

Have a look at the question:
255 x 5

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

Then, multiply each of the numbers by 5.

5 x 200 = 1 000
5 x 50 = 250
5 x 5 = 25

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

multiplication grid: 255 x 5

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

multiplication grid: 255 x 5 = 1275

So 255 x 5 = 1 275

Remember: check the answer by doing the opposite!
1 275 ÷ 5 = 255

Now have a look at this question:
255 x 25

First, split the numbers up and put them in the table:
255 splits into 200, 50 and 5. These go along the top.
25 splits into 20 and 5. These go down the sides.

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

multiplication grid: 255 x 25

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

multiplication grid: 255 x 25 = 6375

255 x 25 = 6 375

Try this method out in the game!


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