SOLUTION: If the police have 9 suspects, how many different ways can they select 5 for a lineup?

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Question 541540: If the police have 9 suspects, how many different ways can they select 5 for a lineup?


Answer by oberobic(2304) About Me  (Show Source):
You can put this solution on YOUR website!
Assuming the order does not matter, you want the number of combinations of 9 things taken 5 at a time.
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The combinations may be denoted as: C(9,5), 9C5 and in several other ways.
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The 5! terms cancel
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+%289%2A8%2A7%2A6%29%2F%284%2A3%2A2%29+=+9%2A7%2A2+
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The above change is because 4*2 cancels the 8 in the numerator and 6/3 = 2
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+9%2A7%2A2+=+126+
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Done.