\begin{definition}[Definition:Plane Number/Similar Numbers]
Let $m$ and $n$ be plane numbers.
Let:
:$m = p_1 \times p_2$ where $p_1 \le p_2$
:$n = q_1 \times q_2$ where $q_1 \le q_2$
Then $m$ and $n$ are '''similar''' {{iff}}:
:$p_1 : q_1 = p_2 : q_2$
That is:
:$\dfrac {p_1} {q_1} = \dfrac {p_2} {q_2}$
{{EuclidSaid}}
:''{{Definition:Euclid's Definitions - Book VII/21 - Similar Numbers}}''
{{EuclidDefRefNocat|VII|21|Similar Numbers}}
Category:Definitions/Euclidean Number Theory
\end{definition}