Question 32
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5 points are marked on one line and 6 points on a parallel line. How many triangles have their vertices among these 11 points?
- A 135 Correct
- B 165
- C 150
- D 120
Correct Answer: Option A
All triples: 11C3 = 165
Collinear triples: 5C3 + 6C3 = 10 + 20 = 30
165 − 30 = 135
Answer: 135
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