In a given circle, draw a chord of given direction and length.
The set of chords of a given length encloses a circle whose radius is $r^{2}=R^{2}-l^{2}$, where $R$ is the radius of the given circle and $l$ is the length of the given chord. The tangents drawn parallel to the given direction to the aforementioned circle serve as the solution to the problem.

(Krausz Mihály, secondary school. VII. grade. Budapest).

The problem was also solved by: Friedmann Bernát, Grünhut Béla, Imre János, Jorga Gergely, Meitner Elemér, Reif Jenő, Visnya Aladár and Weisz Lipót.