Seven points lie on a circle. How many chords can be drawn by joining these points.

12points lie on a circle. How many cyclic quadrilaterals can be drawn by using these points ?

If 20 points are marked on a circle, how many chords can be drawn?

How many chords can be drawn through 21 points?

How many chords we can draw a circle?

Given three distinct points in a plane, how many lines can be drawn by joining them?

Given three distinct points in a plane, how many lines can be drawn by joining them?

Seventeen points are marked on plane so that no three points are collinear. How many straight lines can be formed by joining these points?