Reducing Fractions (Simplest Form)

A fraction is in simplest form if the greatest common factor (GCF) of its numerator and denominator is 1.

For example,

is in simplest form, since 3 and 11 have no common factors other than 1. However,

is not in simplest form, since 6 and 21 share a common factor of 3.

To reduce a fraction, divide both the numerator and denominator by the GCF.

This is sometimes shown as "canceling" the common factors.

Note that the result is an equivalent fraction in simplest form.