What determines the value of a digit in our numbering system?

In our numbering system, the value of a digit is determined by its position within a number. This concept is known as the base or positional value system, which is a foundational element of mathematics, particularly in base-10, or decimal, systems.

For instance, in the number 534, the digit '5' represents five hundreds due to its position, while the '3' represents thirty because it is in the tens position, and the '4' represents four as it sits in the ones position. This illustrates that the same digit can represent different values based solely on where it is located in relation to other digits.

Understanding positional value is crucial for performing arithmetic operations and interpreting numerical data accurately. Therefore, the correct answer emphasizes the importance of a digit's position in determining its value in any given number.