Fakename <fakename@[EMAIL PROTECTED]
> wrote:
: If you toss 100 coins, what's the probability of getting 5 (either heads
or
: tails in a row)? 6 in a row?
: How do you figure it out?
If I'm following the question correctly.
Each toss has an equal chance 50/50 (1:2 or 1/2) of being heads or tails.
If the first toss is heads, the odds of the second toss still has
a 50/50 chance of being heads.
Tosses 1 and 2:
H H
H T
T H
T T
There are four combinations (2 choices raised to 2 tosses), with
2 of them yielding all Heads or Tails. So your chances are
2 out of the 4 combinations will be the same. 2/4 = 1/2 = 50%
If you toss the coin a third time:
H H H
H H T
H T H
H T T
T H H
T H T
T T H
T T T
You wind up with 8 combinations, 2 raised to the 3rd power, with
2 of those 8 being all the same.
So if you were to toss it 5 times you would have 32 combinations,
2^5 (64 combinations if you wanted 6 in a row). With 2 of them
being all the same.
With 5 coins: 2:32 = 1:16 = 6.25%
With 6 coins: 2:64 = 1:32 = 3.125%
--
-davec
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