Final answer:
The total number of possible ZIP Codes without using zero and the letter O is 59,049, which is calculated as 9 to the power of 5 (9^5).
Step-by-step explanation:
The question is about how many possible ZIP Codes there are if zero and the letter O cannot be used. In the United States, ZIP Codes are five-digit numbers, so we need to calculate how many combinations we can have with the digits 1-9 for five places, since zero is excluded.
Normally, with all 10 digits available, we would have 10^5 or 100,000 possible combinations for ZIP Codes. However, with zero excluded from the options, we only have 9 choices for each digit position.
Therefore, the calculation for the total number of possible ZIP Codes would be 9^5, as each of the five positions in the ZIP Code can be filled with any of the 9 remaining digits. So the total number of possible ZIP Codes is 9 * 9 * 9 * 9 * 9, which equals 59,049 possible ZIP Codes without using the digit zero.