isi-entrance 2016 Q43

isi-entrance · India · UGA 4 marks Number Theory Combinatorial Number Theory and Counting
The number of triplets $(a, b, c)$ of integers such that $a < b < c$ and $a, b, c$ are sides of a triangle with perimeter 21 is
(A) 7
(B) 8
(C) 11
(D) 12
The number of triplets $(a, b, c)$ of integers such that $a < b < c$ and $a, b, c$ are sides of a triangle with perimeter 21 is\\
(A) 7\\
(B) 8\\
(C) 11\\
(D) 12