Question

What can be the minimum and maximum number of triangles we can have from 6 points.
A) 0, 15
B) 2, 15
C) 0, 20
D) 2, 20

Answer 1

if 6. points are collinear ( same line )

we have 0 triangle

minimum value is 0

if no 3 points are not collinear we get maximum number of triangle

selection of 3 points among 6 points give one triangle

so number of selection of 3 points from 6 points =6C3=6×5×4/(1×2×3)=5×4=20

so answer. C )0 ,20