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Seven horses are entered in a race. If five horses are tied for first place, and there are no ties among the other two

horses, in how many ways can the seven horses cross the finish line

User Rasheedah
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1 Answer

5 votes

Explanation:

the way I understand it, this means in how many ways can we pick 2 of the 7 horses, when the sequence of these 2 horses matters, but the sequence of the remaining 5 horses does not matter (as they finishing tied or not even starting is in that sense the same thing).

so, we are looking for the permutations of 2 out of 7 elements.

that is

7! / (7-2)! = 7×6 = 42

there are 42 different ways for these 7 horses to cross the finish line in the described constellation.

User Adrita Sharma
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