Three people play badminton and pass it to each other. Everyone can only kick once at a time, starting with kicking. After five passes, the shuttlecock was kicked back to A, so there are (10) different ways of passing.
The analysis is as follows:
From the first pass, A can kick to B or C.
On the second pass, the shuttlecock can kick to A and C; A, b
The third time, the shuttlecock can kick to B and C; Party A and Party B; b,C; a,c;
The fourth level, if the shuttlecock is here at this time, then you can kick 2 people; If the shuttlecock is not here at this time, it can only be kicked to another person 1 who is not A, so it can be kicked to: c; b; b,C; c; c; b; b,C; b; *** 10 possibilities
The fifth level can only kick back to A, and the options are only 1.
So there are 10 different delivery methods.
I wish you progress in your study!
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