Ten points are marked on a straight-line and 11 points are marked on another straight-line
Ten points are marked on a straight-line and 11 points are marked on another straight-line. How many triangles can be constructed with vertices from among the above points?
- 495
- 550
- 1045
- 2475
Answer
Triangle can be formed by taking any two points of a straight line and third point on the second straight line.
10C2 × 11 + 11C2 × 10 = (45 x 11) + (55 x 10) = 1045
The correct option is C.