Can you solve the frog riddle? - Derek Abbott

What people said

Recommends Fabich · 2016-03 · Mathematics Stack Exchange · on “Basic probability : the frog riddle - what are the chances?”

A few days ago I was watching this video The frog riddle [this video] and I have been thinking a lot about this riddle. In this riddle you are poisoned and need to lick a female frog to survive. There are 2 frogs behind you and basically, you have to find what are your chances to find a least one female in these two frogs (you can lick both of them). The only thing is : you know one of them is a male (because your heard the croak) but you don't know witch one. The video solves the problem with conditional probability and explains that you have a 2/3 chance of getting a female. (on the four possibilities MM / MF / FM / FF, knowing there is a male eliminates FF) Here is my question : If you see whi

Recommends eJunior · 2017-01 · Mathematics Stack Exchange · on “Boy girl paradox and information”

I was watching a TED video [this video] about the boy/girl paradox and several questions come up and there are several things I dont understand. Why is there a paradox? In the TED video they say its 1/3 invariabily, But the ODDs for a frog croaking wouldnt be doubled on the Male/Male subgroup? Meaning the correct answer would be 1/2? Isnt the same with the original boy/girl paradox? John Smith have two children, he introduces one of them as a boy. Wich are the odds the other is also a boy? If he is introducing at random isnt introducing a boy the double the odds in the boy/boy subgroup? [BB; BG; GB; GG] arent the odds: [50;25;25;0]? Isnt it showing exactly this? When you take the probabilities of

Cites Jean Carlos Suárez Marranzini · 2016-06 · Mathematics Stack Exchange · on “Probability problem”

I created this problem based on the following probability riddle here [this video] . You're a king, and you were given two groups of people, and a certain information about them. First group has 2 people . One of them is 100% certain to be guilty of a crime. The other one is 50% likely to be guilty and 50% likely to be innocent, and you don't know which one is which. Second group is composed by only 1 person . That person is 50% likely to be guilty of a crime and 50% likely to be innocent. Now you need to imprison either the first group or the second group. By choosing the first group, what is the probability that you imprison an innocent person? What if you imprison the second group? My thought

Cites GambitSquared · 2016-09 · Mathematics Stack Exchange · on “Frog-riddle: What if you can only lick one frog?”

Question about the famous frog-riddle: [this video] What if you can lick only one of the two frogs on the left? I would say that then your chances of survival are 25%: 50% for choosing the frog that didn't croak, times 50% for that frog having the right gender. Is this correct? (If so then I should in that case go for the frog on the right)

Cites Grigoryants Artem · 2017-01 · Mathematics Stack Exchange · on “Is (relatively) popular frog riddle correct from real life point?”

You are standing in a forest and have just eaten a very deadly mushroom which will kill you in a short while. Fortunately magic frogs inhabit the forest of which a lick on the female frog cure all ills, while the male frogs do nothing but croak (the females do not croak). The females and males look identical and the probability of a frog being born a male is $50\%$. You spot a frog at a distance ahead of you. Before you start running towards it, you hear a croak behind you. As you turn around, you see two frogs. You only have time to run and lick either the one in front of you or the two behind you. Which direction should you choose? The question was inspired by watching a TED-Ed Youtube-vid

Cites user514014 · 2019-04 · Mathematics Stack Exchange · on “A variant of the boy/girl paradox”

Some friends and I were arguing about the two following word problems, which are variants of the classic boy/girl paradox [LINK] . (i) "Mrs.Smith lives in a world where the eldest child is always male. She has two children, one older and one younger (although you do not know which is which). What is the probability that they are both male?" (ii) "Mrs.Smith has two children, one older and one younger (although you do not know which is which). The eldest child is male. What is the probability that they are both male?" You can assume that being the eldest child is independent of being male in this problem. My answer to (i) was $\frac{1}{3}$ and to (ii) $\frac{1}{2}$ . My friends believe the ans

Cites user514014 · 2019-04 · Mathematics Stack Exchange · on “A variant of the boy/girl paradox”

I agree with your first comment and have edited my question accordingly. Your second comment gets at what I'm suspecting is my mistake. So suppose we agree that the answer to both (i) and (ii) is $\frac{1}{2}$. Then my follow-up question is as follows: In [LINK] , shouldn't the correct probability that one of the two frogs on the left is male be $\frac{1}{2}$ as well? I follow-up in a subsequent comment.

Cites Daniel · 2020-04 · Mathematics Stack Exchange · on “On the boy-girl paradox and the TED-ed frog riddle”

I'm aware this question has been asked many times - however, I feel I have a different take on the topic. First, let's take a classic scenario. Here, a doctor has 2 babies. He checks both of their genders and tells the nurse "at least one of them is male". Here, the odds babies are both boys is clearly 1/3. Next, let's spin this scenario. Here, the doctor still has 2 babies. He checks only one of their genders (you are unsure which one) and tells you "at least one of them is male". Here, the odds the babies are both boys is clearly 1/2. (unless I'm wrong here) Finally, let me pose my question: does the frame of reference from which you are acquiring the information impact the statistics? In

Cites user819279 · 2020-12 · Mathematics Stack Exchange · on “A couple has two children. At least one is a boy. What is the probability that the couple has one child of each sex?”

"at least" 1 as in 1 or 2, instead of none (0) or both(2) or exactly 1 (1) boys. So there isn't a "the other one" because you don't know 'which' of the two mentioned is for sure a boy. If you haven't done so, check out the flawed probability "frog-licking" video [this video] which is somewhat counterintuitive for opposite reasons as this one.

Critical Albert Renshaw · 2016-03 · Mathematics Stack Exchange · on “The three-coin-flip riddle”

Is the following true (It seems obvious to me that it's not... but... a PhD in physics, Derek Abbott , seems to think others explanation at end of post ): Someone flips 3 coins on the table, they are then covered with paper so I can't see. Two of the coins are on the left of the table, one coin is on the right of the table. I go to the left of the table and start to slide the paper back slowly, eventually revealing the first of the two coins, if it's tails I just have the person re-flip, but if it's heads then I predict the other coin is tails and continue pulling the paper back to reveal tails 66% of the time. Ted-ed (a TED talks division) published a video recently via Physics PHD Derek Ab