COMEDK · Maths · 4. Permutation Combination
There are 12 points in a plane out of which 3 points are collinear. How many straight lines can be drawn by joining any two of them?
- A 60
- B 64
- C 72
- D 84
Answer & Solution
Correct Answer
(B) 64
Step-by-step Solution
Detailed explanation
The total number of ways to select 2 points out of 12 points is given by \(^{12}C_{2}\). \(^{12}C_{2} = \dfrac{12 \times 11}{2 \times 1} = 66\). Since 3 points are collinear, joining any two of these 3 points results in the same line. The number of lines formed by these 3 points…
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