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Algebra II H Problem of the Day H.W. worksheet and p. 941 19-39 odds. Beth, Jill, Angel, and Lenny found 4 seats together at a crowded theater. If Jill insists on sitting next to Lenny, in how many ways can they be seated?. Permutation - an arrangement of a set of distinct
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Algebra II H Problem of the Day H.W. worksheet and p. 941 19-39 odds Beth, Jill, Angel, and Lenny found 4 seats together at a crowded theater. If Jill insists on sitting next to Lenny, in how many ways can they be seated?
Permutation- an arrangement of a set of distinct objects in a certain order. Ex. Set of objects { A, B, C, D} ABCD BACD DCBA BCAD Each of these is a permutation of the set { A, B, C, D}. How many permutations of the set are possible? If you have n objects, the number of possible permutations is n! *Note: Permutations can be found using The Counting Principle
A permutation is not always arranging all of the items in the given group. Ex. Use the 10 digits to make a 4 digit code with no repetition of digits. Counting Principle - 10 * 9 * 8 * 7 = 5040 OR Permutation Formula: n- is the size of the set of items from which you are choosing items to arrange. r- is the number of items you are arranging.
Counting Principle - 10 * 9 * 8 * 7 = 5040 Permutation Formula:
Use the n P r button when n and r are large otherwise the Counting Principle is just as easy. Ex. You have 115 pictures to place in a photo album. The album has 20 pages. Each page hold one picture. In how many ways can the album be filled?
If the items to be arranged are not all unique, we need to account for the repeats. Ex. Find the number of unique arrangements for the word honk and hook. Given n objects with a alike and b alike, the number of distinguishablepermutations of the n objects is:
Permutations with repetitions is also called finding the number of partitions. Ex. A group of 10 students is assigned to complete cleaning tasks around the school during detention. Five are needed to clean desks, 3 to paint parking bumbers, and 2 to pick up trash in the locker tunnel and lunch area. In how many ways can the students be assigned the cleaning duties?