Problem 1015

Daily Math Challenge - October 12, 2023



You have 6 fair coins and 4 unfair coins. Each coin is denoted with heads on one side and tails on the other side.  When a fair coin is flipped, it comes up heads with a probability of 0.5.  When an unfair coin is flipped, it comes up heads with a probability of 0.8.  You place all 10 coins in a bag and randomly select one coin out of the bag without looking.  What is the probability that the selected coin will come up tails when flipped?

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