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bmwhype2
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A coach will make 3 substitutions. The team has 11 players, 29 Oct 2007, 10:01
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A coach will make 3 substitutions. The team has 11 players, among which there are 2 forwards. What is the probability that none of the forwards will be substituted?


Please explain your logic.



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A coach will make 3 substitutions. The team has 11 players, 29 Oct 2007, 10:20
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isnt this just (9 C 3)? or am i missing something here
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A coach will make 3 substitutions. The team has 11 players, 29 Oct 2007, 10:30
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bmwhype2
A coach will make 3 substitutions. The team has 11 players, among which there are 2 forwards. What is the probability that none of the forwards will be substituted?


Please explain your logic.
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not sure if this is correct but i get 52/55

none of forwards substituted =
1 - all forwards picked

total possible = 11C3 = 11!/ 3!8! => 11*10*9 / 3*2*1 = 55

2 forwards picked = 3C2 = 3

1 - 3/55 = 52/55
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A coach will make 3 substitutions. The team has 11 players, 29 Oct 2007, 10:30
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thats what im thinking, 9!/3!6!.................................don't know if it's that easy tho
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A coach will make 3 substitutions. The team has 11 players, 31 Oct 2007, 12:29
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bmwhype2
A coach will make 3 substitutions. The team has 11 players, among which there are 2 forwards. What is the probability that none of the forwards will be substituted?


Please explain your logic.
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desired scenario / total possibilities


9C3 / 11C3
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A coach will make 3 substitutions. The team has 11 players, 31 Oct 2007, 15:01
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There are 9*8*7 ways to arrange 3 substitutes that are not forwards. There are 11*10*9 ways to arrange all the players including substitutes. Hence the probability of selecting only players that are not forward is 9*8*7/11*10*9 = 28/55. Someone correct this if wrong.
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A coach will make 3 substitutions. The team has 11 players, 31 Oct 2007, 16:13
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A coach will make 3 substitutions. The team has 11 players, among which there are 2 forwards. What is the probability that none of the forwards will be substituted?


Please explain your logic.
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Prob(3 substituted but none is forward) = Prob(Pick 1st) x Prob(Pick 2nd) x Prob(Pick 3rd)
= (9/11)x(8/10)x(7/9) = 28/55

Or
Prob = N(Events)/N(Sample Space)
= (9C3)/(11C3) = 28/55



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Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
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