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On May 17 2008 03:35 KarlSberg~ wrote:+ Show Spoiler +
Does the poison take exactly 2 hours to kill a rat?
If so, give a dose from a different jar each 3.6 seconds to the same rat. See when it dies, substract 2 hours and you know exactly at what time it drank the poisoned milk.
Well I must admit it doesn't seem very feasible in a real situation... but nothing in the ridle forbids says it is not =)
I've fixed the problem description such that you do not know exactly how long it takes the poison to kill the rat.
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On May 17 2008 03:35 Slithe wrote:
After 2 hours, these three rats will die, and you will know that it had to be the 50th jar, because no other jar had exactly these 3 rats drink from it.
ohhh wait i see where I'm off I think
ok I get how you guys did it lol
math is neato
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Elements is 100% right, that's the right answer
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The 3 rats did drink from other jars but...
For example let's take jar 51. binary = 0000110011.
In this case, the 1st, 2nd, 5th, and 6th rat drank from it. Thus if the 51st jar was poisoned, then these 4 rats will die. You know it's not the 50th jar because the 1st rat died. Each jar has a unique combination of rats that drank from it, and as a result you can figure out exactly which jar it is based on which of the 10 rats died.
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the binary is just confusing me lol
but don't worry I get it now, thanks for being patient dude 
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lol travis come on XD
i didnt know the answer but i knew which answer to raise my eyebrows to and which to frown and audibly "tch" at
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Yeah the binary is probably just making it harder to understand if you haven't worked with it a lot. My explanations have a natural computer science bias, especially since I get most of my puzzles from other CS majors.
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All you need is one rat. You just have to get really really lucky.
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this was a nice math question 
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the poison takes a nondeterministic amount of time between 2 and 3 hours to kill a rat.
lol. that's so poorly worded: it's possible for none of the rats to die within the 3 hours you have, especially given the fact that your actions don't take ... zero seconds.
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On May 17 2008 03:25 travis wrote:Show nested quote +On May 17 2008 03:23 Elements wrote:On May 17 2008 03:19 travis wrote:On May 17 2008 03:17 Elements wrote:+ Show Spoiler +log2(1000) rounded up equals 10 rats.
Each milk is fed to a unique subset of the rats, depending on which subset dies, then you know the milk it came from was poisoned. With 10 rats, there are 2^10 = 1024 different subsets, which is enough. you have a time limit. (even though i think this answer is what he wanted the correct answer to the riddle to be, he just made the time limit wrong ) The time limit is no problem, you do it simultanously. An example might be better: + Show Spoiler +with 4 jars and 2 rats,
rat 1 drinks jar 2 and 4
rat 2 drinks jar 3 and 4
two hours later...
if no rats die, it was jar 1
if only rat 1 dies, it was jar 2
if only rat 2 dies, it was jar 3
if both rat 1 and rat 2 die, it was jar 4
yes but u have to wait 2 hours so by the time u get it narrowed down to less jars, you have no time let to do a second wave of experiments
you dont do a second round :O
you just use exceptions
if you have 2 rats and feed them like so:
rat 1 - jar 2 and 3
rat 2 - jar 3 and 4
if no rats die (and one of those 4 jars has to have poison) then jar 1 (the one not used) was the poison.
if jar 2 is poison, only rat 1 will die
if jar 3 is poison rat 1 and 2 will both die
if jar 4 is poison only rat 2 will die
I think its something like that, but on a larger scale
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On May 17 2008 03:46 Slithe wrote:
The 3 rats did drink from other jars but...
For example let's take jar 51. binary = 0000110011.
In this case, the 1st, 2nd, 5th, and 6th rat drank from it. Thus if the 51st jar was poisoned, then these 4 rats will die. You know it's not the 50th jar because the 1st rat died. Each jar has a unique combination of rats that drank from it, and as a result you can figure out exactly which jar it is based on which of the 10 rats died.
I really like this explanation
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On May 17 2008 04:25 paper wrote:Show nested quote +the poison takes a nondeterministic amount of time between 2 and 3 hours to kill a rat. lol. that's so poorly worded: it's possible for none of the rats to die within the 3 hours you have, especially given the fact that your actions don't take ... zero seconds.
Contrary to what you may think, your actions do indeed take exactly zero seconds. It's pretty awesome.
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You should have used something cute like puppies or bunnies. Rats, I just want to kill them, thus would not be motivated to not feed them all poison.
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Hong Kong20321 Posts
im sorta confused still but then i never really lked math but i half get it so its ok :D cool stuf
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On May 17 2008 04:26 fusionsdf wrote:Show nested quote +On May 17 2008 03:25 travis wrote:On May 17 2008 03:23 Elements wrote:On May 17 2008 03:19 travis wrote:On May 17 2008 03:17 Elements wrote:+ Show Spoiler +log2(1000) rounded up equals 10 rats.
Each milk is fed to a unique subset of the rats, depending on which subset dies, then you know the milk it came from was poisoned. With 10 rats, there are 2^10 = 1024 different subsets, which is enough. you have a time limit. (even though i think this answer is what he wanted the correct answer to the riddle to be, he just made the time limit wrong ) The time limit is no problem, you do it simultanously. An example might be better: + Show Spoiler +with 4 jars and 2 rats,
rat 1 drinks jar 2 and 4
rat 2 drinks jar 3 and 4
two hours later...
if no rats die, it was jar 1
if only rat 1 dies, it was jar 2
if only rat 2 dies, it was jar 3
if both rat 1 and rat 2 die, it was jar 4
yes but u have to wait 2 hours so by the time u get it narrowed down to less jars, you have no time let to do a second wave of experiments you dont do a second round :O you just use exceptions if you have 2 rats and feed them like so: rat 1 - jar 2 and 3 rat 2 - jar 3 and 4 if no rats die (and one of those 4 jars has to have poison) then jar 1 (the one not used) was the poison. if jar 2 is poison, only rat 1 will die if jar 3 is poison rat 1 and 2 will both die if jar 4 is poison only rat 2 will die I think its something like that, but on a larger scale
ur like 80 years late
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You could mix all the milk into 1 jar. Then you would only need 1 rat to find out the answer.
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This is a nice way to explain hashing
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United States20667 Posts
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EPT
