Note that a negative number is below 0, and a positive number is above 0
Therefore, all negative numbers are less than the positive numbers
Rewriting the numbers :
-22, -6, -13, 15, 18
Now, for negative numbers, the smaller the number, the greater the value.
For example :
-1 > -4
-2 > -5
It is the opposite in the regular number.
So rewriting again the numbers from least to greatest.
-22, -13, -6, 15, 18