Title: "Permutations and the Fundamental Principle of Counting"
Fundamental Principle of Counting (FPCI) states that an activity can be done in n ways; if one activity can be done in n1 ways and another activity can be done in n2 ways, then the activities can be done simultaneously in n1 * n2 ways; and if there are no activities, then there are 0 ways.
N-Factorial (n!) - the product of the positive integers less than or equal to n; n(n-1)(n-2)...(3)(2)(1).
Permutation - an ordered arrangement of objects.
Circular Permutation - the different possible arrangements of objects in a circle (n-1)!
Distinguishable Permutations - refers to the permutations of a set of objects where some of them are alike.
Example: How many different lunches can Joyce choose in their canteen if she has a choice of fried plain rice, chicken adobo, beef caldereta, pork sinigang for the viand, and water, juice, soft drink, and milk tea for beverages?
Illustration:
Rice: Fried, Plain
Viand: Chicken Adobo, Beef Caldereta, Pork Sinigang
Beverages: Water, Juice, Soft Drink, Milk Tea
By listing method, the possible arrangements are:
1. Plain rice, Chicken adobo, Water
2. Plain rice, Chicken adobo, Juice
3. Plain rice, Chicken adobo, Soft drink
4. Plain rice, Chicken adobo, Milk tea
5. Plain rice, Beef caldereta, Water
6. Plain rice, Beef caldereta, Juice
7. Plain rice, Beef caldereta, Soft drink
8. Plain rice, Beef caldereta, Milk tea
9. Plain rice, Pork sinigang, Water
10. Plain rice, Pork sinigang, Juice
11. Plain rice, Pork sinigang, Soft drink
12. Plain rice, Pork sinigang, Milk tea
13. Fried rice, Chicken adobo, Water
14. Fried rice, Chicken adobo, Juice
15. Fried rice, Chicken adobo, Soft drink
16. Fried rice, Chicken adobo, Milk tea
17. Fried rice, Beef caldereta, Water
18. Fried rice, Beef caldereta, Juice
19. Fried rice, Beef caldereta, Soft drink
20. Fried rice, Beef caldereta, Milk tea
21. Fried rice, Pork sinigang, Water
22. Fried rice, Pork sinigang, Juice
23. Fried rice, Pork sinigang, Soft drink
24. Fried rice, Pork sinigang, Milk tea
By the Fundamental Principle of Counting (FPCI): 2 * 3 * 4 = 24 ways