Count Backwards to include Negative Numbers (1)

Starting at 0 we can count up in units like this:

0    1    2    3    4    5    6    7 ...

But what happens before zero?

We have the negative numbers, like this:

...  -7    -6    -5    -4    -3    -2    -1    0

That was counting UP (the numbers are increasing)

Now let's count BACKWARDS from 7 (the numbers are decreasing)

7    6    5    4    3    2    1    0      -1    -2    -3    -4    -5    -6    -7 ...

Example

Count backwards to work out the missing number.

4    3    2    1    0    -1        -3

What is the missing number?

Answer

Counting backwards from 0, it goes:

... 0    -1    -2    -3 

So the missing number is -2.