Tree Diagrams, 12.5

• The counting principle states: If a first experiment can be performed in m ways and a second experiment in n ways, then the two experiments, in that order can be performed in m×n ways.
• one way to illustrate this is with a tree diagram.
  • This allows us to explore the sample space. (a list of all possible outcomes)
  • It is not so useful when m or n are large.
• The probability that an event happens at least once is 1-P(does not happen)
• Do 9, 10, 11 page 713

Permutations, 12.8

• Do problem 22, 23 page 742
• A permutation is an ordered arrangement of a set of objects.
• n! = n * n-1 * n-2 * ... * 2 * 1
• 0! = 0
• Do 3!, 7!, 0!,
• For n items there are n! permutations.
• To select fewer than the full set, use _nP_r
• _nP_r = n!/(n-r)!
• Do problems 28, 31, 32, 33, ...