Probability Map
by rachel hanes
1. Fundamental Counting Rule
1.1. m*n
1.2. Number of ways multiple events can occur.
2. Factorial Rule
2.1. n!
2.2. Number of different permutations.
3. Permutations rule (when all items are different)
3.1. n!/(n-r)!
3.2. Number of permutations when a certain number of items (n) are available, but only a few of them (r) are selected without replacement.
4. Permutations rule (when some items are identical)
4.1. n!/n1!n2!.....nk!
4.2. Number of permutations when a certain number is available, but only a few are used without replacement and some of the items are the same.
5. Combinations rule
5.1. n!/(n-r)!r!
5.2. Number of different combinations when a certain number is available, but only a few are used without replacement. *Order does not matter*