# Points on a Plane 2

Fifteen points $$P_1,P_2,\ldots,P_{15}$$ are drawn in the plane in a such way that besides $$P_1,P_2,P_3,P_4,P_5$$ which are collinear,no other $$3$$ points are collinear.Find the number of triangles whose vertices are $$3$$ of the $$15$$ points.

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