COMEDK2023Evening ShiftMathematicsProbabilityActual
18 Points are indicated on the perimeter of a triangle ABC as shown below. If three points are chosen then probability that it will from a triangle is
Options
- A1 2
- B711 816
- C355 408
- D331 816
Correct answer
B. 711 816
Step-by-step solution
Total points on perimeter = 18 , with 7 points on each side (including vertices). Total ways to choose 3 points = 18 3 = 18 17 16 6 = 816 3 points are collinear (don't form a triangle) only when all 3 lie on the same side. Collinear sets per side = 7 3 = 7 6 5 6 = 35 Total collinear sets = 3 35 = 105 Favourable outcomes (triangles) = 816 - 105 = 711 Probability = 711 816