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7.3 Combinations
Selections in which order is irrelevant, the nCr count, and the test for deciding whether a question wants arrangements or plain subsets.
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4 exercises
7.3 Exercise 1
For each of the following situations, decide whether the chosen subset is a permutation or a combination.
- A social club selects 3 members to form a committee. Each of the members has an equal share of responsibility.
- You are prompted to reset your email password; you select a password consisting of 10 characters without repeats.
- At a dog show, the judge must choose first-, second-, and third-plac…
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7.3 Exercise 3
Compute the following:
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7.3 Exercise 5
- In the card game Texas Hold’em (a variation of poker), players are dealt 2 cards from a standard deck to form their hands. How many different hands are possible?
- The board game Clue uses a deck of 21 cards. If 3 people are playing, each person gets 6 cards for their hand. How many different 6-card Clue hands are possible?
- Palmetto Cash 5 is a game offered by the South Carolina Education Lottery.…
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7.3 Exercise 7
The student government at a university consists of 10 seniors, 8 juniors, 6 sophomores, and 4 first-years.
- How many ways are there to choose a committee of 8 people from this group?
- How many ways are to choose a committee of 8 people if the committee must consist of 2 people from each class?
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Adapted from Contemporary Mathematics © 2023 Rice University. Licensed under CC BY 4.0. Source: Contemporary Mathematics. Imported at revision fa7c1a1.