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If John throws a coin until a series of three consecutive heads or three consecutive tails appears, what is the probability that the game will end after the fourth throw?

How much ever I think about this problem, I am not getting (C). I am getting the answer as 2/16=1/8.

Probability of getting 3 consecutive heads and game ending in 4th turn is THHH = 1/16 Probability of getting 3 consecutive tails and game ending in 4th turn is HTTT = 1/16

1/16 + 1/16 = 1/8

What am I doing wrong???? This probability is a torture

Hi, Your solution is absolutely right! I guess you were confused by the copyright symbol (C) in the post above. It is not an OE.

sdrandom1 wrote:

How much ever I think about this problem, I am not getting (C). I am getting the answer as 2/16=1/8.

Probability of getting 3 consecutive heads and game ending in 4th turn is THHH = 1/16 Probability of getting 3 consecutive tails and game ending in 4th turn is HTTT = 1/16

1/16 + 1/16 = 1/8

What am I doing wrong???? This probability is a torture

Make sure you read the post in the last link carefully before posting another question in this forum.

Thank you for cooperation

pmal04 wrote:

If John throws a coin until a series of three consecutive heads or three consecutive tails appears, what is the probability that the game will end after the fourth throw?