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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Meet The Creators
- Educator Derek Abbott
- Script Editor Alex Gendler
- Director Outis
- Narrator Addison Anderson
Joris Van Houtven
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The answer is wrong. For the frogs in the clearing the chance of survival is 50%. All other explanations for why 50% is the correct answer are ALSO wrong!
The order of the sexes does not matter, since you lick both of them anyway. The male-female case and the female-male case are identical cases in what you call the sample space. So there are only 3 options: one where both frogs are male, one where both frogs are female, and one where one frog is male while the other is female. Now you can eliminate the case where both are female (as in the video) and you end up with a 50% probability of survival (either the frog that didn't croak is a female or a male) when you run to the two frogs, as well as when you run to the single frog. The other explanations are also wrong: croaking frequency doesnt matter, and which of the two frogs croaked doesnt matter either, since you lick BOTH of them!
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