tricky probe-ability! (1 Viewer)

roosterman

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Please help

1a) in how many ways can 3 horses win 1st, 2nd, and 3rd places in a race (trifecta) if there are 8 horses?

b)if i choose different selections of 3 horses, find the probability that i chose the horse that win the first 3 places.
 

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1a) in how many ways can 3 horses win 1st, 2nd, and 3rd places in a race (trifecta) if there are 8 horses?

I think this is a permutation - 8P3, or 8!/(8-3)! - 336 ways.


I_F
 

i4ct

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1a) in how many ways can 3 horses win 1st, 2nd, and 3rd places in a race (trifecta) if there are 8 horses?

This is actualy a combination question, because the combination probability of 3 horses winning 1,2,3 in any order.
therefore answer: 8C3 = 56 ways :p
 

ephemeral

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I'm pretty sure it's 336. A trifecta at the races with 8 horses in it costs $336.
 

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Order matters in this question - a result of ABC is not the same as BCA, since different horse have come 1st, 2nd, and 3rd. If order didn't matter, then it would be a combination.


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Sober

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i4ct said:
1a) in how many ways can 3 horses win 1st, 2nd, and 3rd places in a race (trifecta) if there are 8 horses?

This is actualy a combination question, because the combination probability of 3 horses winning 1,2,3 in any order.
therefore answer: 8C3 = 56 ways :p
That's a boxed trifecta
 

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