1. Permutations and Combinations
Unit 6 Continued…

2. Definitions Permutations – order important Combinations – any order
You need to know n! (“n factorial”)
Ex: 4! =
Ex: 7! =

3. Formulas Permutations Combinations r = items chosen
n = total possible items

4. Example 1
Suppose you have four personalized letters and four addressed envelopes. If the letters are randomly placed in the envelopes, what is the probability that all four letters will go to the correct addresses?
This is order important – permutation

5. Example 2
In a “pick 6” lottery, 54 numbered balls are used. Out of these, 6 are randomly chosen. To win, at least 3 balls must be matched in any order. What is the probability of winning the jackpot (all 6 balls)?

6. Same groups as yesterday!
Work on assignment together!
I will be marking off points for people who are not using their time wisely or talking about other things!