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- ACCUPLACER Test Prep
- Permutations and Combinations
Permutation vs. Combination
- Lesson: 141:38
Permutation vs. Combination
Basic Concepts: Organizing outcomes, Probability of independent events, Simplifying rational expressions and restrictions, Solving rational equations
Lessons
- permutation: nPr = number of arrangements of "r" items taken from a set of
"n" distinct items (order matters!!)
= (n−r)!n!
- combination: nCr = number of selections of "r" items taken from a set of "n" distinct items (order does NOT matter!!) = (n−r)!r!n!
- combination: nCr = number of selections of "r" items taken from a set of "n" distinct items (order does NOT matter!!) = (n−r)!r!n!
- 1.a) How many ways can two prizes be awarded to a class of 5 students?
• 1st prize = $100
• 2nd prize = $5
b) How many ways can two identical movie tickets be awarded to a class of 5 students?