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April 27th, 2018, 02:22 AM   #1
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How to understand this solution?

In how many ways can a team of four be selected from eight players?

1) When one player is always included? 2) When one player is always excluded?

Solution: 1) Since one player is always included, then we have to select three players from seven which can be done in 7C3 ways.

2) Since one player is always excluded then we have to select 4 players from 7 which can be done in 7C4 ways.

My question: why in both cases 7 is taken instead of 8?

I mean 7C3 and 7C4 etc.
Ganesh Ujwal is offline  
 
April 27th, 2018, 04:07 AM   #2
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In the first problem "one player is always included" so we select the remaining 3 players from the other 7.

In the second problem "one play is always excluded" so we can ignore him and choose all four players from the other 7.

Last edited by skipjack; April 27th, 2018 at 06:44 AM.
Country Boy is offline  
April 27th, 2018, 06:47 AM   #3
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The question is unclear anyway, as "team" isn't defined.
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