In how many ways can you sit 8 people on a bench if 5 of them must sit together?	Options
A) 720
B) 2,160
C) 2,880
D) 4,320
E) 40,320
In such questions, always tie the person that have to sit together. So we have effectively 3+1= 
<gadget id="calculator">3+1</gadget>
<output>4</output>
4 persons to arrange.   They can be arranged in 4! ways.   Now the 5 persons can themselves be arranged in 5! ways.   Total ways: 4!*5!= 2880.   2,880 is the answer.
<result>C</result>
In how many ways can you sit 8 people on a bench if 5 of them must sit together?