Multiplying large numbers by splitting

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Multiplying large numbers by splitting
Created by: Sabrina Edmondson Adapted from BBC online

Multiplying large numbers by splitting
Have a look at the following equation: 255 x 5

Multiplying large numbers by splitting
First split the number into hundreds, tens and ones. 255 splits into 200, 50 and 5

Multiplying large numbers by splitting
Then, multiply each of the numbers by x 200 = x 50 = x 5 = 25

Multiplying large numbers by splitting
This method can be represented in a grid, as shown below.

Multiplying large numbers by splitting

Multiplying large numbers by splitting
So 255 x 5 = 1,275 Remember: check the answer by doing the opposite! 1,275 ÷ 5 = 255

Multiplying large numbers by splitting
Now have a look at this equation: 255 x 25

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)

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.

Multiplying large numbers by splitting
Add up each column, then add the resulting numbers together. + +

Multiplying large numbers by splitting
So 255 x 25 = 6,375 Remember: check the answer by doing the opposite! 6,375 ÷ 25 = 255