Find the number of triangles which can be formed by joining the angular points of a polygon of 8 sides as vertices.
A. 56
B. 24
C. 16
D. 8
Answer: Option A
Solution(By Examveda Team)
A triangle needs 3 points. And polygon of 8 sides has 8 angular points. Hence, number of triangle formed, $$\eqalign{ & { = ^8}{{\text{C}}_3} \cr & = \frac{{8 \times 7 \times 6}}{{1 \times 2 \times 3}} \cr & = 56 \cr} $$Join The Discussion
Comments ( 1 )
Related Questions on Permutation and Combination
A. 3! 4! 8! 4!
B. 3! 8!
C. 4! 4!
D. 8! 4! 4!
A. 7560,60,1680
B. 7890,120,650
C. 7650,200,4444
D. None of these
A. 8 × 9!
B. 8 × 8!
C. 7 × 9!
D. 9 × 8!
The number of triangles that can be formed by joining the angular points of a polygon of n sides as vertices are n(n-1)(n-2)/6