Question 1098616: A fisherman has 13 different trout flies. How many different selections of 7 flies each can he make?
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! A fisherman has 13 different trout flies. How many different selections of 7 flies each can he make?
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Label them A thru M.
The 1st pick is 1 of 13.
then 1 of 12
Then 1 of 11
etc
--> 13*12*11*10*9*8*7
= a big number
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But, choosing A, B, C ... & K is the same as choosing B, K, C, A ...
---> 7*6*5*4*3*2*1 ways to choose any combination.
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So the possibilities are 13*12*11*10*9*8*7/(7*6*5*4*3*2*1)
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You can calculate that, or use
13!/(13-7)!*7!)
= 1716 ways
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