Q. In how many ways can 5 boys and 5 girls sit in a circle so that no two boys sit together?
A) $5! \times 5!$
B) $4! \times 5!$
C) $\frac{5! \times 5!}{2}$
D) None of these
Explanation
(b)
First we fix the alternate position of the girls. Five girls can be seated around the circle in $(5 - 1)! = 4!$, 5 boys can be seated in five vacant place by $5!$
$\therefore$ Required number of ways$= 4! \times 5!$
[image:7_image6.emf]
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.