Question
Question: The sides AB, BC, CA of a triangle ABC have 3, 4, 5 interior points respectively on them. Total numb...
The sides AB, BC, CA of a triangle ABC have 3, 4, 5 interior points respectively on them. Total number of triangles that can be formed using these points as vertices, is equal to
A
135
B
145
C
178
D
205
Answer
205
Explanation
Solution
Total triangles = 12C3 – 3C3 – 4C3 – 5C3