Euclid:Proposition/VII/13

Proposition

In the words of Euclid:

If four numbers be proportional, they will also be proportional alternately.

(The Elements: Book $\text{VII}$: Proposition $13$)

Sources

• 1926: Sir Thomas L. Heath: Euclid: The Thirteen Books of The Elements: Volume 2 (2nd ed.) ... (previous) ... (next): Book $\text{VII}$. Propositions