How To Multiply Numbers # 1
There's a limit to the number of multiplication facts that can be remembered so we need step-by-step methods for multiplication with larger numbers. There is more than one method including the one shown below and this other way of multiplying numbers.
Multiplication - one way
| 3 x 13 | ||
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o
o o o o o o o o o o o o
o
o o o o o o o o o o o o
o
o o o o o o o o o o o o |
We can split the 3 groups of 13 into: Think of 13 in its expanded form. e.g. 3 + 10 |
o
o o
o
o o
o
o o
o
o o o o o o o o o
o
o o o o o o o o o
o
o o o o o o o o o |
3 groups of 13 |
is the same as | 3 groups of 3 |
3 x 3 plus 3 x 10 3 x 13 = 39 |
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Watch
this animated example with explanations showing how to multiply 15 x 7 using the method above.
As shown in the following examples, we can write our multiplication calculation, by breaking the number to be multiplied into its expanded form.
| 13 x 3 | ||||||||||||
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| Multiply the ones | Put a zero in the ones' place as we're multiplying tens | Add the products to get the answer | ||||||||||
| 13 x 3 = 39 | ||||||||||||
| 47 x 4 | ||||||||||||
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| Multiply the ones | Put a zero in the ones' place as we are multiplying tens | Add the products to get the answer | ||||||||||
| 47 x 4 = 188 | ||||||||||||
| 318 x 6 | |||||||||||||||
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| Multiply the ones | Put a zero in the ones place (as we are multiplying tens) and multiply the tens | Put two zeros in the ones' and tens' places | Multiply the hundreds and add to get the answer | ||||||||||||
| 318 x 6 = 1908 | |||||||||||||||
Try the worksheets below for more practice with multiplying using the method shown above.
2
x 1 digit - Products to 99 e.g. 23 x 2- 2
x 1 digit - Products to 999 e.g. 93 x 4
- 2
x 1 digit - regrouping e.g. 73 x 7
- 3
x 1 digit e.g. 436 x 7
You'll find more free multiplication worksheets here.
More Math Help