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JEE Mains · Maths · STD 11 - 6. permutation and combination
On the sides \(AB, BC, CA\) of a \(\Delta ABC, 3, 4, 5\) distinct points ( excluding vertices \(A, B, C\)) are respectively chosen. The number of triangles that can be constructed using these chosen points as vertices are
- A \(210\)
- B \(205\)
- C \(215\)
- D \(220\)
Answer & Solution
Correct Answer
(B) \(205\)
Step-by-step Solution
Detailed explanation
Required number of triangles \(= \,^{12}C_3 - (^3C_3 + ^4C_3 + ^5C_3 )\, = 205\)
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