Twenty points are marked on a plane so that non three points are collinear except 7 points. How many triangle can be formed by joining the points?

Twelve points are marked on a plane so that no three points are collinear. How many different triangles can be formed joining the points.

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

There are 12 points in a plane, no three points are collinear except 6 points. How many different triangles can be formed?

Sixty points lie on a plane, out of which no three points are collinear. How many straight lines can be formed by joining pairs of points ?

There are 15 points in a plane. No three points are collinear except 5 points. How many different straight lines can be formed?

Out of 18 points in a plane, no three are in the same line except 5 points which are collinear How many triangles can be formed by joining the given points.

There are 20 points in a plane, of which 5 points are collinear and no other combination of 3 points are collinear. How many different triangles can be formed by joining these points?

How many triangles can be formed by joining 6 points lying on a circle ?

Out of 18 points in a plane, no three are in the same line except 5 points which are collinear How many straight lines can be formed by joining the given points?