In this instructable, I will teach you an easy method I created for multiplying numbers between 1 and 100 with relative ease.

All I ask is that you have a decent understanding of math

**Signing Up**

## Step 1: Pick two numbers

## Step 2: Dissect the numbers

19 x (10 + ((1/2) 10))

or

15 x (20 - 1)

Now the first one might seem a little harder, but it's really not. If you have a five in the equation, you can simply multiply a number by 10 (which is simple, just add a 0 at the end), and then take half of it. So 19 x 5 = half of 19 x 10.

That means that 19 x 5 = (1/2) 190

But for now, let's just stick with the second equation because it is simpler.

## Step 3: Multiply out

The distributive property states that we can distribute the 15 to the other numbers, meaning we have (15 x 20) - (15 x 1)

I am sorry for these really short pages, btw.

## Step 4: Do some more simple math

Since multiplication has the commutative property, it doesn't matter what order we multiply the numbers in. 15 x 10 x 2 is exactly the same as 10 x 2 x 15, and 2 x 15 x 10, using that rule, we can find that:

2 x (15 x 10) = 2 x 150 = 300

and since we still have to subtract 15 x 1 (which equals 15), we just subtract 15 from 300, giving us 285

Great instructable. These free customizable worksheets are great for practicing multiplication: http://stemsheets.com/math/multiplication-worksheets

21

23

There are the 3 steps:

a) Multiply vertically on the left: 2 x 2 = 4.

This gives the first figure of the answer.

b) Multiply diagonally and add: 2 x 3 + 1 x 2 = 8

This gives the middle figure.

c) Multiply vertically on the right: 1 x 3 = 3

This gives the last figure of the answer.

Final answer = 483

Works for any two 2 digit numbers. Sometime you have to carry numbers but its still easy. You know how you read about people who can multiply huge numbers? This is how they do it.