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Probability of getting three heads in five tosses of two coins?

  1. Apr 17, 2013 #1
    This statement seems to me to be similar to something like : the number of trials is 10 and the expected number of heads is 3. What is the difference between these two, if there is any? And although the second seems to be a simple case of binomial distribution, I wonder how one would go about tackling the first situation.
  2. jcsd
  3. Apr 17, 2013 #2


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    hi s0ft! :smile:
    i'm tempted to say that if you toss two coins, you'll never get three heads, no matter how many times you toss them! :rolleyes:

    ignoring that interpretation, yes the two statements mean exactly the same :smile:
  4. Apr 17, 2013 #3


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    You seem to be confusing the probability of a given outcome (three heads in five tosses) with the average over a number of tosses. Unless the coin is biased, the average after ten tosses should be five.
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