A coin is tossed three times: The probability of zero heads is 1/8 and the probability of zero tails

slijmigrd 2022-07-07 Answered
A coin is tossed three times: The probability of zero heads is 1/8 and the probability of zero tails is 1/8.

And my question is: What is the probability that all three tosses result in the same outcome?

So, if P(zero heads)= 1/8 , then that should be the same of p(all tails)?

If so, we could use the Addition Rule which is P ( A B ) = P ( A ) + P ( B )

where A and B are disjoint events, i.e. A A B = , A is the event of tossing all heads and B is the event of tossing all tails.

I'm not sure how to continue after that... would the complement be used?
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Answers (1)

Jayvion Tyler
Answered 2022-07-08 Author has 23 answers
Let A be the desired event. Then
P ( A ) = P ( H H H ) + P ( T T T ) = 1 8 + 1 8 = 1 4 .
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