Probability

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Probability

by ajmoney09 » Tue Jun 09, 2009 8:19 pm
A roulette wheel consists of 38 slots. 36 of these are
numbered 1 through 36 and colored red or black so
that there are nine red even-numbered slots, nine black
odd-numbered slots, etc. These slots occur with equal
probability. The two slots marked 0 or 00 are each
three times as likely to occur as any one of the other
36. What is the probability that a red even number, a
red 23, or a 00 will occur on one roll of the wheel?


The answer is 13/42.

Someone please explain this to me, thanks.
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by tohellandback » Tue Jun 09, 2009 10:51 pm
How can there be a red numbered 23? it must be even. or don't I understand the question?

if it were just 23 and not red 23:

total probable events are 36+(2*3)
because 0 and 00 are three times as likely to occur as anyof the other 36

probabily of a red= 9/42

probability of a 23=1/42

probabilty of 00=3/42

Adding up-13/42

adding up- 13/42
The powers of two are bloody impolite!!