JEE PYQ

[JEE Main 2013] t n is the number of triangles from an n gon if t n

VAVidaara Admin Asked 2d ago 0 views 1 answer
#PYQJEE#JEE#JEE Main#2013#geometrical-counting#Permutations and Combinations

$T_n$ is the number of triangles from an $n$-gon. If $T_{n+1}-T_n=10$, then $n$ is

(a) $7$
(b) $5$
(c) $10$
(d) $8$

1 Answer

VAVidaara Admin ✓ Vidaara Team ✓ Accepted · 2d ago ▲ 0

Correct answer: (b) $5$

$\binom n2=10\Rightarrow n(n-1)=20\Rightarrow n=5$.

JEE Main 2013 · Permutations and Combinations — verified solution by the Vidaara Team.

Log in to post your own answer or join the discussion.

Discussion (0)

No comments yet — start the discussion.

← Back to all questions