Question

If 20 lines are drawn in a plane such that no two of them are parallel and no three are concurrent, in how many points will they intersect each other?

Answer 1

It is given that no two lines are parallel which means that all the lines are intersecting and no three lines are concurrent.

One point of intersection is created by two straight lines.

Number of points of intersection = Number of combinations of 20 straight lines taken two at a time