Let

be a triangle, and let

,

,

be three points in the interiors of the sides

,

,

of this triangle. Prove that the area of at least one of the three triangles

,

,

is less than or equal to one quarter of the area of triangle

.
Alternative formulation: Let

be a triangle, and let

,

,

be three points on the segments

,

,

, respectively. Prove that

,
where the abbreviation

denotes the (non-directed) area of an arbitrary triangle

.
%V0
Let $ABC$ be a triangle, and let $P$, $Q$, $R$ be three points in the interiors of the sides $BC$, $CA$, $AB$ of this triangle. Prove that the area of at least one of the three triangles $AQR$, $BRP$, $CPQ$ is less than or equal to one quarter of the area of triangle $ABC$.
Alternative formulation: Let $ABC$ be a triangle, and let $P$, $Q$, $R$ be three points on the segments $BC$, $CA$, $AB$, respectively. Prove that
$\min\left\{\left|AQR\right|,\left|BRP\right|,\left|CPQ\right|\right\}\leq\frac14\cdot\left|ABC\right|$,
where the abbreviation $\left|P_1P_2P_3\right|$ denotes the (non-directed) area of an arbitrary triangle $P_1P_2P_3$.