Which of the following best describes a divisor?

A divisor is defined as a number that divides another number without leaving a remainder. In mathematical terms, if you have a dividend (the number being divided) and you divide it by a divisor, the result is called the quotient. The key aspect of a divisor is that it is responsible for determining how many times a number can be contained within another number or how many groups can be formed.

For example, in the division 12 ÷ 3 = 4, the number 3 is the divisor because it divides 12 evenly, resulting in a quotient of 4. This understanding is foundational in arithmetic and helps in performing operations efficiently.

The other descriptions do not accurately capture the role of a divisor. For instance, describing a divisor as the number being divided refers to the dividend, not the divisor itself. The result of the division refers to the quotient rather than the divisor, and the sum of the dividend and divisor does not relate to the concept of division at all.