A group of n people, including Caroline and her best friend Catherine, stand in random order
around a circle, with each order being equally likely. If the probability that Catherine is adjacent
to Caroline is 1/9 , then what is the value of n?  Choose the correct choice from the following answers:	A) 20	B) 19	C) 18	D) 17	E) 16
Caroline is adjacent to 2 people, and there are n 􀀀 1 people not including Caroline.   Therefore, the probability that Catherine is adjacent to Caroline is 2/n-1 = 1/9 , and solving gives   n = 19 .   correct answer 19
<result>B</result>
A group of n people, including Caroline and her best friend Catherine, stand in random order
around a circle, with each order being equally likely. If the probability that Catherine is adjacent
to Caroline is 1/9 , then what is the value of n?