AP EAMCET · Maths · Permutation Combination
Find the number of marked points on the plane, if when connected pairwise by line segments, the total number of line segments formed is
- A
- B
- C
- D
Answer & Solution
Correct Answer
(C)
Step-by-step Solution
Detailed explanation
Let there be n points on the plane, then the number of line segments=nc2 nc2=15 ⇒n(n-1)2=15 ⇒n(n-1)=30 ⇒n=6
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