12 persons are seated around a round table. What is the probability that two particular persons sit together ?

Question

astrophysics · Answer

Lets draw a diagram first |dw:1447831996223:dw| looks like the sun! Anyways, so probability is just $$Probability = \frac{ \text{number of favourable outcomes} }{\text {number of possible outcomes} }$$

anonymous · Answer

possible outcomes is 11!

anonymous · Answer

No. of favorable outcomes?

astrophysics · Answer

It says, that two persons sit together, 11! is the number of ways they can sit around the table but it's not for two people right, so we have 10! instead

astrophysics · Answer

And number of possible outcomes is 11

anonymous · Answer

But answer is 2/11

astrophysics · Answer

11!*

astrophysics · Answer

Yes so $$\frac{ 10! \times 2! }{ 11! }$$

anonymous · Answer

Oh okay. thank you @Astrophysics  :)

anonymous · Answer

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