1955 AHSME Problems/Problem 6
A merchant buys a number of oranges at for cents and an equal number at for cents. To "break even" he must sell all at:
Since we are buying at for cents and for cents, let's assume that together, we are buying 15 oranges. That means that we are getting a total of oranges for cents. That comes to a total of oranges for cents. = . This leads us to for cents which is and we are done. -Brudder