Which tool is used as an aid in solving HEX subtraction problems?

The addition table serves as an effective tool for solving HEX subtraction problems because subtraction in any number system, including hexadecimal (HEX), can be approached through the concept of addition. In the context of HEX, subtraction can be reinterpreted as adding the additive inverse.

When you need to subtract one HEX number from another, you can find the complement of the number being subtracted and then add it to the first number. An addition table allows for quick reference of sums within the HEX system, facilitating this process. By using the addition table, you can easily look up the required values to perform the subtraction tasks, making it an essential tool in simplifying calculations and reducing errors.

Other tools like a binary calculator or multiplication tables do not provide direct support or simplification for HEX subtraction, while decimal notation is irrelevant in the context of performing operations specifically within the HEX system.