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.

^{10}C_{2} × 11 + ^{11}C_{2} × 10 = (45 x 11) + (55 x 10) = 1045

**The correct option is C.**