Can you solve the frog riddle? - Derek Abbott
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You’re stranded in a rainforest, and you’ve eaten a poisonous mushroom. To save your life, you need an antidote excreted by a certain species of frog. Unfortunately, only the female frog produces the antidote. The male and female look identical, but the male frog has a distinctive croak. Derek Abbott shows how to use conditional probability to make sure you lick the right frog and get out alive.
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Lesson in progress
50%. Bernulli trial approach
The approach with the sample space in the video is wrong, because order doesn't matter as many noticed. What we actually have here is a bernulli trial with number of trials =2 (n=2). If X = the number of female frogs in the 2 trials, the possibility you want to calculate is at least one female among the 2 or P (X>=1). The information you have is at least 1 of the 2 is male so you know X<2). The conditional probability is P((X>=1)/(X<2)) = P(X=1) = (2! / 1!(2-1)!) * (0.5^1) * (1-0.5)^(2-1) = 2*0.5*0.5 = 0.5 = 50% So the answer is 50%.
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