Six boys and six girls sit in a row at random. Find the probability that
(a) the six girls sit together
(b) the boys and girls sit alternatively.

Question

Six boys and six girls sit in a row at random. Find the probability that
(a) the six girls sit together
(b) the boys and girls sit alternatively.

anonymous · Answer

Try simplifying the problem and work backwards, what if it was 2boys and 2 girls?

ankit042 · Answer

total ways to arrange 12!
girls sit together : 7C1*6!*6!
(7c1 to select the seats for girls and then arrange boys with 6!. The second 6! is for arranging girls)

uri · Answer

@ankit042 How do we get 7C1?

ankit042 · Answer

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Girls can have seven different positions