SOLUTION: Determine if the problem is a combination or permutation and then find the answer. How many ways can a group of 5 people be chosen from a class of 20?

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Question 553588: Determine if the problem is a combination or permutation and then find the answer.
How many ways can a group of 5 people be chosen from a class of 20?
Answer by AnlytcPhil(1806) About Me  (Show Source):
You can put this solution on YOUR website!
The combinations of 20 things taken 5 at a time

That can be written any of the following ways:

"20 Choose 5", 

C(20,5), 

20C5,

C20,5

20C5

20C5

20 nCr 5   <--(The TI-83 or TI-84 notation)

%28matrix%282%2C1%2C20%2C5%29%29 

Answer %2820%2A19%2A18%2A17%2A15%29%2F%285%2A4%2A3%2A2%2A1%29 = 1860480%2F120 = 15504


It's 'Combinations' because no pecking order is specified.

[If one had to be president of the group, one vice-president, one secretary,
one treasurer, and one business manager, then it would be permutations.  Or if
they had to sit in five chairs and it mattered who sat where, it would be
permutations.  But order is not important, so it's "combinations"].

Edwin