Tough and Tricky questions: Combinations.
Nine students - 4 boys and 5 girls - are to sit side by side for a makeup exam. How many ways could they arrange themselves given that no two boys and no two girls can sit next to one another?
Select:
A) 12 B) 36 C) 72 D) 240 E) 5760
4!*5!*2 = 24*120*2= 
<gadget id="calculator">24*120*2</gadget>
<output>5_760</output>
5760 ways.   Ans. 5760) 5760
<result>E</result>
Tough and Tricky questions: Combinations.
Nine students - 4 boys and 5 girls - are to sit side by side for a makeup exam. How many ways could they arrange themselves given that no two boys and no two girls can sit next to one another?