Final answer:
The arithmetic average of -12%, 17%, and 22% is 9%.
Step-by-step explanation:
To find the arithmetic average of a set of numbers, you add up all the numbers and then divide the sum by the total number of numbers. In this case, the numbers are -12%, 17%, and 22%.
The sum of -12%, 17%, and 22% is -12% + 17% + 22% = 27%.
Since there are three numbers in the set, you divide the sum by 3: 27% / 3 = 9%.
Therefore, the arithmetic average of -12%, 17%, and 22% is 9%.