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
by Ryan Peng
Ryan Peng
Lesson in progress
The question is over complicated and the possibility is actually 50%
Video doesn't take in the fact that only a male frog can croak. If you heard one frog croak, that gives you these options Frog 1 male frog2 male, frog one croaks Frog1 male frog2 male, frog two croaks Frog 1 female frog 2 male, frog two croaks Frog 1 male frog two female, frog one croaks Now if it was impossible to find two female frogs but both male and female could croak, the video would be right because then you are getting these other possibilities: Frog1 female frog2 male, frog 1 croaks Frog1 male frog2 female, frog2 croaks If these two possibilities were open it would indeed be 67
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Antonis Tsirilikos
Lesson in progress
If both male and female could croak, it is equivalent to not being any croak at all. Even if we knew which one croaked, wouldnt make any difference.
If it was impossible to find two female frogs, only by making assumptions could lead to 2/3. Why it is impossible to find two female frogs one next to the other?
Assuming any frog is obliged to be in pair with another randomly selected frog and be with that certain frog forever. Also sth happened and all pairs of female-female became extinct at same time you eat the mushroom. In this case I agree with 2/3 answer.
Assuming all frogs walk alone and also can be by chance next to each other. But for some reason a female will never stand next to another female. One frog stands there. It can be male or female 50-50. Then another comes and stand next to it. If the first is male, the other can be male with 50% or female 50%. If the first is female, the other is male 100%. So, it is:
mm: 25%
mf: 25%
fm: 50%
one or two female: 25+50=75%
Yuan Zhang
Lesson in progress
Good insight. A simplified version of the concept was presented by Eric Chen later on and generated 18 responses. Is Conditional Probability necessary for solving the problem at all?
