Question

There are 12 points in a plane in which 6 are collinear. Number of different straight lines that can be drawn by joining them is

• A. 51
• B. 52
• C. 132
• D. 18

Answer 1

Answer: (B)

52

Answer 2

$12C_{2} -^{6}C_{2} + 1 = 66 - 15 + 1 = 52$

(One is added, as from 6 collinear points one line can be drawn).