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Today, we're going to learn a very simple strategy for multiplying 2, 4 and 8.
Strategy for Multiplying by 2
As you know, multiplying by 2 is really easy right?
We have to add the number to itself and we will get the answer.
For example:
1 x 2 = 2 1 + 1 = 2
2 x 2 = 4 2 + 2 = 4
4 x 2 = 8 4 + 4 = 8
8 x 2 = 16 8 + 8 =16
We've doubled these numbers.
Strategy for multiplying a number by 4:
When we multiply a number by 4, we get same result as if we multiplied the number by 2 twice.
For example:
6 x 4 = 24
If we're doing this by 2, it looks like this:
6 x 2 = 12
12 x 2 = 24
Do you notice that if we multiply a number by 2, then we multiply the result by 2, we get the same result as if we times it by four?
Strategy for multiplying a number by 8:
Guess what? In our strategy that we used for multiplying by four also works for multiplying by 8. For eights, we need to multiply the number by 2 thrice (3 times).
For example:
5 x 8 = 40
If we're doing this by 2, it will look like this:
5 x 2 = 10
10 x 2 = 20
20 x 2 = 40
Watch this video to learn your eight multiplications in an easy way.
Strategy for Multiplying by 2
As you know, multiplying by 2 is really easy right?
We have to add the number to itself and we will get the answer.
For example:
1 x 2 = 2 1 + 1 = 2
2 x 2 = 4 2 + 2 = 4
4 x 2 = 8 4 + 4 = 8
8 x 2 = 16 8 + 8 =16
We've doubled these numbers.
Strategy for multiplying a number by 4:
When we multiply a number by 4, we get same result as if we multiplied the number by 2 twice.
For example:
6 x 4 = 24
If we're doing this by 2, it looks like this:
6 x 2 = 12
12 x 2 = 24
Do you notice that if we multiply a number by 2, then we multiply the result by 2, we get the same result as if we times it by four?
Strategy for multiplying a number by 8:
Guess what? In our strategy that we used for multiplying by four also works for multiplying by 8. For eights, we need to multiply the number by 2 thrice (3 times).
For example:
5 x 8 = 40
If we're doing this by 2, it will look like this:
5 x 2 = 10
10 x 2 = 20
20 x 2 = 40
Watch this video to learn your eight multiplications in an easy way.
Ready for the next step on your road to becoming an amazing math wiz?