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Six people lined up to shoot the math problem in Grade Two, 1. If it is divided into two rows, two in the front row and four in the back row, how many are there? ...
1 is actually divided into two rows, regardless of the number of people in each row. In fact, it can be arranged directly in 720.

There are two situations (Party A and Party B) where Party A and Party B are put together into a whole by binding, and then this is.

The whole and the remaining four people are completely arranged, which is 2*(5*4*3*2* 1)=240.

By inserting an empty method or calling a partition method.

Three boys can't be adjacent, and there must be a girl in the middle. (Note that girls can be adjacent, that is to say, two girls can be used to separate boys, and one girl can also be used to separate boys. )

Boys have 3*2* 1=6.

There are two situations in which girls are not adjacent, A4 is 3=24.

There are two girls next to each other. C3 needs two arrangements and A2 needs two girls. The arrangement of C3 is 2 times A2 and 2 times A2 and 2= 12.

So there are 24+ 12=36 kinds of girls.

So a * * * permutation is 6*36=2 16.