The simplest form of a fraction is
$\,\displaystyle\frac{N}{D}\,$, where
$\,N\,$ and
$\,D\,$ have no
common factors (except
$\,1\,$).
Thus, in simplest form, there is no number other than
$\,1\,$ that goes into both
the numerator and denominator evenly.
EXAMPLES:
Question:
Write in simplest form:
$\displaystyle\frac{6}{15}$
Solution:
The fraction
$\,\frac{6}{15}\,$ is not in simplest form, because $\,6\,$ and $\,15\,$
have a common factor of $\,\bf{3}\,$.
To simplify the fraction, use the following thought process:

$6\,\,\,$ divided by $\,\bf{3}\,$ is $\,2\,$ (the new numerator is $\,2\,$)

$15\,$ divided by $\,\bf{3}\,$ is $\,5\,$ (the new denominator is $\,5\,$)
 Thus,
$\,\frac{6}{15} = \frac{6\div\bf{3}}{15\div\bf{3}} = \frac{2}{5}\,$.
 Since
$\,2\,$ and $\,5\,$ have no common factor other than $1$,
the simplest form of
$\,\frac{6}{15}\,$ is
$\,\frac{2}{5}\,$.
Note:
$\displaystyle\frac{6}{15} \ \ = \ \ \frac{3\cdot 2}{3\cdot 5} \ \ = \ \ \frac{3}{3}\cdot\frac{2}{5}
\ \ = \ \ 1\cdot\frac{2}{5} \ \ = \ \ \frac{2}{5}\,$
Thus, simplifying a fraction is just getting rid of extra factor(s) of $\,1\,$.
Question:
Write in simplest form: $\frac{2}{6}$
Answer:
$\frac{1}{3}$
In the exercises below, you will input fractions using a forward diagonal slash.
For example,
$\,\frac{1}{3}\,$ is input as 1/3 .