Which term describes a number that can be expressed in the form a/b where a and b are whole numbers and b does not equal zero?

The term that describes a number that can be expressed in the form a/b, where 'a' and 'b' are whole numbers and 'b' is not equal to zero, is known as a fraction. A fraction represents a part of a whole and consists of a numerator (the number on top, 'a') and a denominator (the number on the bottom, 'b'). This definition is central to the concept of fractions in mathematics, as it explicitly defines the relationship between the two numbers with the requirement that the denominator cannot be zero, since division by zero is undefined.

In contrast, integers refer to whole numbers that can be positive, negative, or zero, but do not include fractions or decimals. Whole numbers are a subset of integers that include zero and all positive integers but exclude negative numbers and fractions. Decimals represent numbers that can also express fractions but are written in decimal notation, which does not align with the specified form of a/b given in the question. Thus, the definition perfectly aligns with the understanding and structure of fractions.