I have four sizes, each are in a hash by their square feet:

```
# The sizes. Sizes are in sq ft (min, max)
size_hash = {
  'Large'  => [70,139],
  'Medium' => [15,69],
  'Small'  => [1,14]
}

```

If I'm given the number `40`, how can I return `Medium` as the size from the array?

Do I need to do something like this?:

```
# The sizes. Sizes are in sq ft (min, max)
size_hash = {
  [70..139]  => 'Large',
  #... etc
}

```