NOTES 10 -5
n stands for total number of items
r is how many items you are choosing
Oct 27­3:22 PM
Permutation or Combination?
Ex 1
A home security device with 10 buttons is
disarmed when 3 different buttons are
pushed in proper sequence. (No button can
be pushed twice). How many different
codes can be entered?
What if you can repeat?
Oct 29­8:53 AM
Oct 29­9:00 AM
Permutation or Combination?
Ex 2
Five students (Bob, Carol, Donna, Ed, and
Joe) have volunteered for service to the
student government.
a)
If 3 of the students are to be
selected for a special committee, how
many different committees are
possible?
b)
If 3 of the students are to be
nominated for the offices of
president, vice president, and
secretary, how many different slates
are possible?
Oct 29­9:02 AM
1
Permutation or Combination?
Ex 3
a)
For a 9-person baseball team about to
play, how many ways can you list the
first 6 players in the batting order?
Ex 4
Over the weekend, your family is going on
b)
vacation, and your mom is letting you bring
your favorite video game console as well as
five of your games. How many ways can you
choose the five games if you have 12 games
in all?
For a 10-person basketball team, how
many ways can you select 4 players to
take part in the pre-game coin toss?
Oct 29­9:05 AM
Ex 5
Suppose you have 12 girls and 10 boys
that want to join a club. You are only
allowed 5 boys and 3 girls. How many
different combinations are possible?
Nov 1­8:05 PM
Oct 29­9:12 AM
HOMEWORK:
pg 549 ­ 550 22 ­ 29 all, READ Example Adding Combinations pg 550 then
Complete 37 ­ 39 all
Oct 29­9:14 AM
2