SOLUTION: There are 20 people who work in a office together. Five of these people are selected to go to a conference. How many selections are possible?

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Question 1023274: There are 20 people who work in a office together. Five of these people are selected to go to a conference. How many selections are possible?
Answer by ikleyn(52800) About Me  (Show Source):
You can put this solution on YOUR website!
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C%5B20%5D%5E5 = %2820%2A19%2A18%2A17%2A16%29%2F%281%2A2%2A3%2A4%2A5%29 = 19*6*17*8 = 15504,

the number of combinations of 20 things taken 5 at a time.

See the lesson Introduction to Combinations in this site.