22: Combinations
- Page ID
- 83521
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- 22.1: Motivation
- How many different four-member study groups could be formed from a class of twenty students?
- 22.2: Basics
- Combination: a finite subset of a given set
- 22.3: Applications
- How many ways are there to distribute seven coins amongst three children? (Assume the coins are indistinguishable. But children are obviously distinguishable.)
- 22.4: Properties
- Note: In this section we will use the alternative notation Cnk in place of C(n,k).