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Math Destroyer 2013
Test 1, # 38
Five chairs are lined up in a row. How many ways can three boys and two girls sit in these chairs if the girls always sit side by side?
I understand that it is 4 x 2(possible side by side configurations of girls) x 3! (Possible configurations of guys) = 48.
What I am wondering, however, is why can't I use permutations and combinations?
For example, why can't i do 5P2 (for the girls) * 3! (For the guys). That answer gives me 60.
Test 1, # 38
Five chairs are lined up in a row. How many ways can three boys and two girls sit in these chairs if the girls always sit side by side?
I understand that it is 4 x 2(possible side by side configurations of girls) x 3! (Possible configurations of guys) = 48.
What I am wondering, however, is why can't I use permutations and combinations?
For example, why can't i do 5P2 (for the girls) * 3! (For the guys). That answer gives me 60.