JEE Main & Advanced
Sample Paper
JEE Main Sample Paper-28
question_answer
On the sides AB, BC, CA of a \[\Delta ABC\], 3,4,5 district points (excluding vertices A,B,C) are respectally chosen. The number of triangles that can be constructed using these chosen points as vertices are
A) 220
B) 215
C) 210
D) 205
Correct Answer:
D
Solution :
Number of triangles \[{{=}^{12}}{{C}_{3}}-(1{{+}^{4}}{{C}_{3}}{{+}^{5}}{{C}_{3}})\]