Explore the following Permutation of Multiset examples to understand how to calculate arrangements in various scenarios.
Example 1: Permutations of a Multiset of Letters
- Problem: How many different ways can you arrange the letters A, A, B, and B?
- Solution: There are 4 letters, with A repeating twice and B repeating twice, 4! / 2! x 2! = 24 / 4 = 6.
- Permutations: {AABB}, {ABAB}, {ABBA}, {BAAB}, {BABA}, {BBAA}.
Example 2: Permutations of a Multiset of Numbers
- Problem: How many different ways can you arrange the numbers 1, 1, 2, and 3?
- Solution: There are 4 numbers, with 1 repeating twice, 4! / 2! = 24 / 2 = 12.
- Permutations: {1123}, {1132}, {1213}, {1231}, {1312}, {1321}, {2113}, {2131}, {2311}, {3112}, {3121}, {3211}.
Example 3: Permutations of a Multiset of Colors
- Problem: How many different ways can you arrange the colors red, red, blue, and green?
- Solution: There are 4 colours, with red repeating twice, 4! / 2! = 24 / 2 = 12.
- Permutations: {red, red, blue, green}, {red, red, green, blue}, {red, blue, red, green}, {red, blue, green, red}, {red, green, red, blue}, {red, green, blue, red}, {blue, red, red, green}, {blue, red, green, red}, {blue, green, red, red}, {green, red, red, blue}, {green, red, blue, red}, {green, blue, red, red}.