Acoin is rigged such that the probability of getting tails is three times that of getting heads. on average, how many coin flips does it take to get two heads in a row?

Probability of tails = 3/4 Probability of heads = 1/4 Say you are going to make two coin flips, the outcomes are HH, TT, HT, TH. The probability of HH is (1/4)*(1/4) = 1/16. On average, it will take 16 trials to get two heads in a row. This will equal 32 coin flips, since each trial is two coin flips.

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