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A coin is biased so that a head is twice as likely to occur as a tail. If the coin is tossed 3 times, then the probability of getting two tails and one head is
(2) 29
P(H)=2P(T) and P(H)+P(T)=1
P(T)= 13, P(H)= 23
∵ tosses are independent and the head can be in any of 3 places (HTT, THT, TTH):
P=3C1 ( 13 )2 ( 23 )=3 227= 29
Answer: (2)
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