SOLUTION: There is a meeting of 31 people. How many ways can one choose a team of two people from those attending the meeting?

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Question 1028811: There is a meeting of 31 people. How many ways can one choose a team of two people from those attending the meeting?
Found 2 solutions by ikleyn, kev82:
Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
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There is a meeting of 31 people. How many ways can one choose a team of two people from those attending the meeting?
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C%5B31%5D%5E2 = %2831%2A30%29%2F%281%2A2%29 = 31*15 = 465 ways.

See the lesson Introduction to Combinations in this site.


Answer by kev82(151) About Me  (Show Source):
You can put this solution on YOUR website!
There are 31 choices for the first person, there are then 30 choices for the second person. However it's the same pair regardless of the order I choose them in (AB = BA) so that gives 30*31/2 = 15*31 = 465.