NIMCET 2016 Question Paper with solutions

Total number of peoples = 9
Number of ways in which 5 people groups can be selected from 9 people
According to the question,
5 people are selected from 9-2 particulars people alreadyin the same group
${\Rightarrow }^9{\mathit{C}}_5{-}^7{\mathit{C}}_3\Rightarrow \frac{9!}{5!4!}-\frac{7!}{3!4!}$
$\Rightarrow \frac{9\times 8\times 7\times 6}{4\times 3\times 2}-\frac{7\times 6\times 5}{3\times 2}\Rightarrow 126-35\Rightarrow 91$