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
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:
3 groups of 3
and 3 groups of 10

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
plus
3 groups of 10

3 x 3 plus 3 x 10
9 + 30

3 x 13 = 39

13 x 3
1 3
x 3
9
1 3
x 3
9
0
1 3
x 3
9
+ 3 0
1 3
x 3
9
+ 3 0
3 9
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
4 7
x 4
2 8
4 7
x 4
2 8
0
4 7
x 4
2 8
+ 1 6 0
4 7
x 4
2 8
+ 1 6 0
1 8 8
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
3 1 8
x 6
4 8
3 1 8
x 6
4 8
0
3 1 8
x 6
4 8
+ 6 0
3 1 8
x 6
4 8
6 0
0 0
3 1 8
x 6
4 8
6 0
+ 1 8 0 0
1 9 0 8
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.

You'll find more free multiplication worksheets here.