Suppose you flip a coin 3 times in a row. How many different sequences of
heads and tails are possible?
2*2*2=8
if you roll two 6 sided dice, how many different outcomes are possible
6*6= 36
Suppose Texas license plates must be 6 characters long and first 3 characters
are either letters or digits and last 3 characters must be digits. How many
possible license plates.
36*36*36*10*10*10= 46,656,000
how many 5 letter passwords can you make from the letters { a,b,c,d,e,f} if
adjacent letters must be different
6*5*5*5*5= 3750
an anagram = a word formed by rearranging the letters in some original
word.
Ex: how many anagrams of “stop”
Pots, tops, spot, psot, tpso, opts
Factorial is a decreasing product of natural numbers down to 1.
(ON PAPER)
Suppose you deal out a sequence of 5 cards from a deck of 52 cards. How
many different 5card choices are there?
52*51*50*49*48…= 311,875,200
Two ways to select a subset of items from one large set of DISTINCT
numbers:
1.
if we care about the order/arrangement of selection then
selection is a permutation.
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2.
2. If we don’t care about the order, then selection is a
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 Spring '11
 Cathy
 Math, license plates, Suppose Texas license, different 5card choices, unordered subset Ex

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