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
Young-Hwan Kim
Lesson in progress
Why does the guy who ate the poisonous mushroom don't go towards the frog that is on the tree?
I think the video only focus on the two frog side. You can still make percentages on the frog on the tree. I think it will be nearly a hundred percent since It dosen't crick.
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Eric Chen
Eric Chen
Lesson in progress
in response to John Price Show comment
Actually, the croaking is not a colorful way of saying that. The croaking makes a huge difference in the probability.
John Price
John Price
Lesson in progress
The problem doesn't state that we know all males that have croaked. We know nothing about frogs that don't croak; only that if a frog croaks, it must be male. Given the frog on the stump has not croaked, we simply know it is silent. It could be male or female at the same probability. Perhaps this species of frog just croaks randomly once a year, and we were lucky enough to hear one of them today.
It also doesn't state anything about croak frequency. If it did (say, it said all males croak randomly at a frequency of once per minute), then if we wait long enough, we could be fairly confident that if the frog on the stump didn't croak, it was female.
But that is adding additional information to the problem (croaking frequency).
The croaking, in this puzzle, is just a colorful way of saying "You have a pair of frogs, and one of the pair is male. What is the chance the pair contains a female frog?"
