Count Backwards to Include Negative Numbers

Starting at 0 we can count up in 2s like this:

0    2    4    6    8    10    12    14 ...

But what happens before zero?

We have the negative numbers, counting in 2s, like this:

...  -14    -12    -10    -8    -6    -4    -2    0

That was counting up.

Now let's count backwards in 2s from 14.

14    12    10    8    6    4    2    0    -2    -4    -6    -8    -10    -12 ...

Example

Count backwards in 2s to work out the missing number.

8    6    4    2    0    -2        -6

What is the missing number?

Answer

Counting backwards in 2s from 0, it goes:

... 0    -2    -4    -6

So the missing number is -4

Can you see the pattern?

Let's try some questions now.