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Probability - coin toss

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Probability - coin toss

by oks » Sat Aug 08, 2009 4:43 pm
What is the probability of getting an identical result on three consecutive tosses of a coin?

a. 1/2
b. 1/4
c. 1/8
d. 1/16
e. 1/2 + 1/4

OA is B. Why not C?

The way I solved it: 3C3/2^3 = 1/8
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by prindaroy » Sat Aug 08, 2009 6:46 pm
HHH = 1/2 * 1/2 * 1/2 = 1/8

TTT = 1/2 * 1/2 * 1/2 = 1/8

1/8 + 1/8 = 2/8 or 1/4
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by tom4lax » Sun Aug 09, 2009 2:04 pm
First coin toss doesnt matter so probability is 1. Next 2 have to be identical to first, so 1/2 probability for each.

1*1/2*1/2 = 1/4
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