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Unfair coin probability question?

You have an unfair coin that comes up heads 80% of the time. What is the probability that you must flip the coin four or more times to get the first tail?

4 Answers

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  • Paula
    Lv 7
    1 decade ago
    Favorite Answer

    p(need 4 or more flips to get 1st tail)

    = p(first 3 flips are all heads)

    = 0.8^3

    = 0.512

  • 1 decade ago

    The probability of 4 heads in a row is just 0.8^4 = 0.4

  • 1 decade ago

    probability that it will come tails any one time is 20% or .2 so we want it to go...heads heads heads tails. so .8 * .8 * .8 * .2 = 10% ish.

  • ?
    Lv 4
    4 years ago

    it extremely is requesting the possibility of each available consequence (heads and tails are the available outcomes of each toss). consistently undergo in ideas that the possibilities of all the available outcomes ought to consistently upload to a million, and on your question heads is thrice lots extra in all probability than tails, so the respond is (d).

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