Question 879972
The way I see it is:
You can have:
BGBGBG
or
GBGBGB
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In the 1st case, you have:
(1) 3 choices for a boy
(2) 3 choices for a girl
(3) 2 remaining choices for a boy
(4) 2 remaining choices for a girl
(5) 1 remaining choice for a boy
(6) 1 remaining choice for a girl
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In the 2nd case, you have:
(1) 3 choices for a girl
(2) 3 choices for a boy
(3) 2 remaining choices for a girl
(4) 2 remaining choices for a boy
(5) 1 remaining choice for a girl
(6) 1 remaining choice for a boy
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Possible seatings total:
{{{ 3*3*2*2*1*1 + 3*3*2*2*1*1 }}}
{{{ 36 + 36 = 72 }}}
72 possible ways