To determine how many employee codes the company has available, let's break down the problem.

Case 1: The ID consists of one uppercase letter followed by a digit.

• The first part (the letter) can be any uppercase letter from the English alphabet. There are 26 uppercase letters (A to Z), so there are 26 possible choices for the first part.
• The second part (the digit) can be any digit from 0 to 9, so there are 10 possible choices for the second part.

Thus, for this case, the total number of employee codes is: $26 \times 10 = 260$

Case 2: The ID consists of two uppercase letters followed by a digit.

• The first letter can be any of the 26 uppercase letters (A to Z), so 26 choices.
• The second letter can also be any of the 26 uppercase letters (A to Z), so another 26 choices.
• The digit can be any of the 10 digits from 0 to 9, so 10 choices.

Thus, for this case, the total number of employee codes is: $26 \times 26 \times 10 = 6760$

Total Number of Employee Codes

Now, to find the total number of employee codes, we add the results from both cases: $260 + 6760 = 7020$

So, the company has 7,020 possible employee codes available.

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Would you like any more details or explanations about this problem?

Here are 5 related questions you might find interesting:

1. How would the total number of codes change if the company allowed three letters instead of one or two?
2. What if the company assigned employee codes with numbers in place of letters? How would that affect the total number of codes?
3. How would the calculation change if the digits in the employee codes could only be even numbers (0, 2, 4, 6, 8)?
4. If the company had to assign codes using lowercase letters instead of uppercase, how many codes would they have?
5. Can you find a way to write a formula for calculating the total number of possible employee codes based on the number of letters allowed?

Tip: When working with combinatorics problems like this, it's helpful to break down the problem into different cases and use multiplication for independent choices (like selecting a letter and a digit).