Q11
There are 10 points in a plane out of which 4 are collinear. Find the number of triangles formed by the points as vertices.
A.
120
B.
116
AnswerC.
140
D.
20
Answer: Option B
Solution
Answer: Option B
Solution:
The number of triangle can be formed by 10 points = 10C3Similarly, the number of triangle can be formed by 4 points when no one is collinear = 4C3
In the question, given 4 points are collinear, Thus, required number of triangle can be formed,
= 10C3 - 4C3
= 120 - 4
= 116