## Range

The range of a set of numbers is the highest number minus the lowest number.
So, in the set { 2, 5, 8, 2, 1, 4, 3 } the highest number is 8 and the lowest number is 1, so the range is
```
8 - 1 = 7 <--range!
```
If there are any negative numbers in the set, then you have to be really careful,
because subtracting a negative number is the same thing as adding the positive number.
So, in the set
```
{ 5  -1  6  -2  0 }
```
The highest number is 6 and the lowest number is - 2, so the range is:
```
6 - (-2) = 6 + 2 = 8 (remember, a minus times a minus is a plus!)
```
Think of it as the distance between 6 and - 2 on the number line, like this:
```
---|---|---|---|---|---|---|---|---|---|---|---|-- ...
-3  -2  -1   0   1   2   3   4   5   6   7   8
|<------------ 8 -------------->|
```

For a more in-depth discussion of range and other statistics, see the statistics notes.

So, here is a problem for you:
What is the range of this set of numbers?
```
{ 9   4   8   9   2   -1   3   4 }
```
Range = _______