Which term is used for a fraction that is expressed in decimal form?

The term "decimal fraction" specifically refers to a fraction that has been converted into decimal form—meaning the numerator is expressed as a decimal rather than as a traditional fraction. This term accurately describes any fraction whose denominator is a power of ten, allowing it to be represented in a base-10 format.

In contrast, other terms may not capture this concept as directly. For example, "decimal part" typically refers to the digits that appear after the decimal point, not the entire fraction itself. "Decimal whole" suggests a complete integer value, which does not apply to fractions being represented in decimal form. The term "fractional number" can encompass a range of values but is less specific than "decimal fraction" in addressing fractions that specifically involve decimal representation.

Thus, the terminology of "decimal fraction" clearly aligns with the question, reinforcing the correct identification of a fraction in its decimal format.