we know that
The centroid is the point where all three medians intersect and divides each median in a ratio of [tex]2:1[/tex]. Is described as the triangle's center of gravity.
In this problem
C-Q, B-P and D-R ------> are medians
The point X is the centroid of the triangle BCD
so
[tex]BX=\frac{2}{3}BP[/tex]
we have
[tex]BP=15\ cm[/tex]
substitute
[tex]BX=\frac{2}{3}(15)=10\ cm[/tex]
therefore
the answer is
[tex]BX=10\ cm[/tex]
