7.3 Permutation or Combination 4/12/2013

In the last lesson (combination) we learned about possible number of combinations where the order in which things are chosen does not matter. Today, we’re going to learn about possible number of combinations where the order in which things are selected DOES matter. It’s called PERMUTATION. Example: Suppose there are 7 swimmers entering a swim meet. Assuming that there are no ties, in how many ways could the gold, silver, and bronze medals be awarded?

You want to take Math, Science and Art during Periods 1, 2 and 3. How many possible arrangements can you have? Period 1Period 2Period 3 1 Math Science Art 2 Math Art Science 3 Science Math Art 4 Science Art Math 5 Art Math Science 6 Art Science Math Period 1 Period 2 Period ● ● = 6

Permutation Definition: How it is written: Formula: Another method:

You want to take Math, Science and Art during Periods 1, 2 and 3. How many possible arrangements can you have?

There are 9 candidates in a city election for mayor. The winner will be the mayor and the runner-up will be the vice mayor. How many different cabinets of mayor and vice- mayor are possible? = 72 MayorVice-Mayor 9 8 ● = 72

Suppose there are 7 swimmers entering a swim meet. Assuming that there are no ties, in how many ways could the gold, silver, and bronze medals be awarded? = 210 ways a medal could be awarded GoldSilver 7 6 ● = 210 Bronze 5 ●

In how many distinct ways can the word STUDY be written? = =

There is a raffle to be held in a classroom of 24 students. If 5 prizes are to be raffled, how many sets of winning students could there be? = 42504

Homework WS 7.3 Skip #2 & 4 I’m reading a book about anti-gravity. I can’t put it down!!!