There are 5 points
P1,P2,P3,P4,P5 on the side
AB, excluding
A and
B, of a triangle
ABC. Similarly there are 6 points
P6,P7,…,P11 on the side
BC and 7 points
P12,P13,…,P18 on the side
CA of the triangle. The number of triangles, that can be formed using the points
P1,P2,…,P18 as vertices, is: