What does it mean for a fraction to be in simplest form?

For a fraction to be in simplest form means that it cannot be reduced any further, which means the numerator and the denominator share no common factors other than 1. This means that the fraction is expressed in its most basic, irreducible state. For example, if you have the fraction 8/12, it can be simplified to 2/3 because both the numerator and the denominator can be divided by 4, which is their greatest common factor. Once simplified to 2/3, there are no common factors left between the numerator and the denominator.

The other choices do not accurately describe what it means for a fraction to be in simplest form. For instance, a numerator of zero means the fraction equals zero, but it doesn’t help in identifying its simplest form. A denominator of one indicates that the number is a whole number rather than a proper fraction, and an improper fraction simply expresses a whole number along with a fraction, which doesn’t speak to the simplification process. Therefore, the characteristic that truly defines a fraction in simplest form is that it cannot be reduced any further.