ITEC 122 2008fall ibarland

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lect13a
counting
products; permutations

# license plates;  
# plates where the first char is a letter;
# passwords of length 5;   #passwords of length 5-or-6-or-7
# of phone#s;    (area code can't start with 0,1, nor be 911)
# credit cards (vs # people in world);
pigeon hole
# of ways to arrange students
# of ways to send our 20 volunteers to one of 50 states.
   with repetitions; without (permutations).
   Combinations: what if you only care which states get a volunteer?

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©2008, Ian Barland, Radford University Last modified 2008.Dec.08 (Mon)

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