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If 8 rooks (castles) are randomly placed on a chessboard, compute the probability that none of the rooks can capture any of the others. That is, compute the probability that no row or file contains more than one rook.

Short Answer

Expert verified

The probability that no row or file contains more than one rook9.109×10-6

Step by step solution

01

Step1

Since rooks attack horizontally & vertically, you can't have a rook in the same row or column as another.

So in the first row, you place a rook. There are 8possible places for first one. In the next row you place a rook,it can't be in the same column as other rook so for this one we have 7possibilities i.e. 8!ways

Now total number of possible ways is648

so the probability that no rooks capturing =6488!=9.109×10-6

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Most popular questions from this chapter

An instructor gives her class a set of 10problems with the information that the final exam will consist of a random selection of 5them. If a student has figured out how to do 7the problems, what is the probability that he or she will answer correctly

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