Screenshot_2018-02-20-08-57-34-1.png
In a $16×16$ chessboard,from the $X$ signed cell, a king starts to move.In one step he can move up,down,right or left one cell.How many ways are there such that he can come back to the $X$ signed cell in $6$ steps?Mymensingh Region Higher Secondary 2017/10
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Please don't post problems (by starting a topic) in the "X: Solved" forums. Those forums are only for showcasing the problems for the convenience of the users. You can always post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
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In a $16×16$ chessboard,from the $X$ signed cell, a king starts to move.In one step he can move up,down,right or left one cell.How many ways are there such that he can come back to the $X$ signed cell in $6$ steps?
Re: Mymensingh Region Higher Secondary 2017/10
Think the case that an Up move will torpedo a Down move whence, a Right move will torpedo a Left move.
Now, count for $4$ moves first, and then for last $2$ moves.
Now, count for $4$ moves first, and then for last $2$ moves.
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Re: Mymensingh Region Higher Secondary 2017/10
samiul_samin wrote: ↑Tue Feb 20, 2018 9:06 amScreenshot_2018-02-20-08-57-34-1.png
In a $16×16$ chessboard,from the $X$ signed cell, a king starts to move.In one step he can move up,down,right or left one cell.How many ways are there such that he can come back to the $X$ signed cell in $6$ steps?