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Coin question

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Coin question

by jfranco23 » Mon Jan 26, 2009 7:24 pm
When tossed, a certain coin has equal probability of landing on either side. If the coin is tossed 3 times, what is the probability of that it will land on the same side each time?

A. 1/8
B. 1/4
C. 1/3
D. 3/8
E. 1/2
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by gaggleofgirls » Mon Jan 26, 2009 7:38 pm
each flip of the coin is independent, so it is
1/2 * 1/2 * 1/2 = 1/8 that all three tosses will be the same.

But there are two of the 8 possibilities that get us three of the same side: HHH and TTT so it is 2/8 or 1/4.

Answer = B

-Carrie
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by vittalgmat » Mon Jan 26, 2009 11:33 pm
2 possibilities: HHH and TTT.
Total possibilities: = 2^3

So probability = 2/2^3 = 2/8 = 1/4

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