Please clarify

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Re: Please clarify

by dtweah » Sat Jun 06, 2009 1:23 pm
nervesofsteel wrote:a coin has an equal probability of landing on either side.
if coin is tossed 3 times, what is the prob that it will land on same side each time ?

A) 1/8
B) 1/4
C) 1/3
D) 3/8
E) 1/2

OA B
Same side can be H or T

1/8+ 1/8=1/4

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by kris610 » Sun Jun 07, 2009 6:29 am
It could be either H or T.

P(H 3 times)+P(T 3 times) = 1/2*1/2*1/2+ 1/2*1/2*1/2 = 1/4.