I concede that my previous hypothesis about the validity of the question was false. The answer isnt TV friendly. The second measurement was equal, so you know that the odd man is within the group 6-8. Put any two groups on each side of the see-saw. Number the men 1,2,312. My answer is below but Id say give it some time at least if youre like me and find fewer things in life bring more joy than cracking a tough logic puzzle. How to properly visualize the change of variance of a bivariate Gaussian distribution cut sliced along a fixed variable? This one comes from this week's Brooklyn Nine-Nine episode! Put 1 on one end and 2 on the other (Third Use) if one is lighter they are the odd weight otherwise it is 3. I gave each of the 12 men a letter, A-L. Can You Solve the Brain Teaser of the 12 Men and a See-Saw? (Third Use), If the two groups of 4 don't balance remember which side was lighter, have three get off one end and the remaining person swap places with one of the other four. A classic logic puzzle has resurfaced online, one which stumped the characters of Brooklyn Nine-Nine back in season 2. Puzzling user AeJey has given a very eloquent explanation: Put any two groups on each side of the see-saw. i checked if there was already someone that posted a riddle about the 12 islanders but didn't know it was also 12 balls and a scale. It is a see saw, not a giant scale! Solution 2b. Otherwise the one who stayed is the oddly weighted one. A seesaw is binary. But this is simple! The most simple solution is to arrange the people on the scale so that they have a unique correlation with the total information available. Learn more. Presented below is a simpler solution. If the weights are equal, then one of A2.4 is heavier; weigh A2 and A3. There is an island with 12 islanders. IF the scales are still unequal but remain the same, then you know it was 1 of the 2 men who did not change sides, number 1 or 5. So, what is the 12 people on an island riddle and what is the answer? by Mikhael Panju v2. seesaw: R1 L2 L3 L4 L1 S2 S3 S4 (balanced) It only takes a minute to sign up. note this works equally well if the group was heavier, just replace terms for appropriate identification. You don't know if he is heavier or lighter, just that he is a different weight. This way of wording will help make it easier to figure out the puzzle. The exciting catch? WRONG! Weigh 5 against 6. Create an account to follow your favorite communities and start taking part in conversations. Can patents be featured/explained in a youtube video i.e. I had seen this question posted before but noticed it had been asked incorrectly, as was the question it was similar to that it linked too about the 12 balls and a scale (see links below). [9, 10, 11] VS. [1, 2, 3]. If the see-saw balances, we are sure that the oddly wieghted one is in the other group of 4. Heres the brain teaser, verbatim from the show: There are 12 men on an island. (Third Use), If the see saw is not balanced, remove one from each end. One problem - you have to figure out which person it is too. If nothing happens, download Xcode and try again. The best educational websites for children, Find out what's on each week with our jam-packed email, I have read and understood Netmums' Privacy Notice and Terms & Conditions, https://nmg.netmums.com/header/activities/, https://www.netmums.com/esi/video/false/position:ATF, https://www.netmums.com/esi/mostactivechat/website/article. Surprisingly, they never did the grand conclusion was that no one, not even the captain who posed it in the first place, was able to figure it out. Proceed to step 2. Learn more about Stack Overflow the company, and our products. Solution 2c. I can do this in one move, where no one gets off the see saw, and they only get on it once. Use the {{3 remaining with known weight solution}} from solution 1a. How do you figure out which one is heavier? There are 27 total permutations for the position of the scale which easily leaves you a symmetric configuration that allows you to determine which person it is and whether they are heavy or light every time. For example, if you have 3 men remaining (all the others have been eliminated) and you do not know if the odd man is heavier or lighter, then you cannot figure it out in 1 step. "There are 12 men on an island. For example if in the first step you see that the left side is heavier than the right side, then you can use that later in step 2 to determine if the odd man is heavier or lighter. L: sit on the left, R: sit on the right, -: dont sit on the seesaw. How do you do it? Thus in principle we can get log227 bits from the three comparisons. sideline: S1 R2 R3 R4, we know that the light islander is amongst R2 R3 R4 The results of that 4x4 measurement will indicate to you to a second specific group of 4 to measure, and from there, only 2. If balanced it is the heavy L1 else if unbalanced it is light R1. It is impossible to know both for sure in only three steps.). Thankyou for reading and understanding. run a simulation: go run . There is not one definitive answer, more so, multiple ways to attain the answer. 11 weigh exactly the same amount, but one of them is slightly lighter or heavier. Death by roo roo. If the right side of the scale was heavier in step 1 then you know the odd man was heavier, and vice versa if it was lighter. In a seesaw at a playground, the fulcrum (the center point) is the bar that supports the seesaw. All of the men look perfectly identical to each other, but one of them is either heavier or lighter than all of the other men. If they are equal then it is the one not being measured and he is heavier. It is a good write up though. if balanced it is L4 - else it is the heavier of L2 and L3. are patent descriptions/images in public domain? You must use a see-saw to figure out whose weight is different, and you may only use the see-saw 3 times. First weigh 1,2,3,4 against 5,6,7,8. Your aim is to find out which person weighs a different amount. 2: Place the man from your pair who was on the lower end of the see-saw . You must figure out which. we weigh S1 against S2. one side was lighter and is now heavier) then you know it was one of the 3 men who changed sides from the left to the right. Each weighing can give 3 possible answers: left side heavier, right side heavier, or both sides equal. The ice cube and the basketball have the same weight. You cant solve this puzzle? 2150 Condos - West Tower Phase 2 Use 1 - Place both groups on opposing sides of the fulcrum, evenly spaced along the lever. If they are the same, 7 is different (and lighter). You can weigh three combinations of men on the see-saw. That person is the heavier (or lighter). (Third Use) Use your second seesaw turn to weigh those four (two on each side) to see which side is heavier. Three measurements in all. Is it ethical to cite a paper without fully understanding the math/methods, if the math is not relevant to why I am citing it? Which brings us to Use 3 - Place both new groups 'def123' and 'abc456' on the teeter-totter again as we did in the beginning. Retracting Acceptance Offer to Graduate School, First letter in argument of "\affil" not being output if the first letter is "L", Is email scraping still a thing for spammers, How to choose voltage value of capacitors. If the see saw is not balanced, remove one from each end. If he is lighter then it is the one being measured and he is lighter. seesaw: R1 L2 L3 L4 L1 S2 S3 S4 (heavy) In 11/12 cases you know whether the person is lighter or heavier as the seasaw dictates it. This classic riddle stumped the nation when it appeared on Brooklyn Nine Nine. rev2023.3.1.43268. So in principle, we should be able to solve the problem. Questions: I actually figured this out on my own this evening while out walking my dog. Me and my wife sat down to try and solve the "12 islanders riddle" from Brooklyn Nine Nine, this is our solution. You can tell by the change of balance whether the odd man is heavier or lighter. 11 of them weigh the same and one of them is either slightly Puzzling Stack Exchange is a question and answer site for those who create, solve, and study puzzles. (named after their starting position, L1 = Left 1, R1 = Right 1, S1 = Side 1 etc..), We now know that the odd islander are amongst S1 S2 S3 S4 If, you want to get the solution and are having trouble, I have published a few TIPS at the bottom of the document. 12 Islanders Teeter Totter Riddle There is an island with 12 islanders. L: sit on the left, R: sit on the right, -: don't sit on the seesaw.. How does a fan in a turbofan engine suck air in? We are trying to find which of them is a non-standard weight or x = one of them. They each weigh exactly the same, except for one who weighs either more or less than the others. ; C1, C2. There is also a see-saw on the island. The second measurement was unequal, but the balance of weight shifted. All of the islanders individually weigh exactly the same amount, except for one, who either weighs more or less than the other 11. seesaw: L1 L2 L3 L4 R1 R2 R3 R4 (balanced) If balanced, the remaining unknonw is the odd one and can be determined in step 3. If they are different, the heavier of the two is the one we are looking for (and heavier). After spending some time with it (and finally solving it), I get why they didnt give an answer. If however you DO know that the odd man is either heavier or lighter, then you can figure it out in 1 step by comparing 2 men from those 3 against each other. Weigh 12 against 1 to find out whether 12 is heaver or lighter. There are no scales or other weighing device on. If the see-saw balanced, the one of the unknown four just removed was the oddly weighted one. You can only use it three times. The best answers are voted up and rise to the top, Not the answer you're looking for? 12 Islanders Riddle Puzzle from Brooklyn 99. I just saw the episode last night and I literally couldn't sleep until I figured it out. Before you read on, I just want to say that this problem drove me nuts. Each islander is given a position to sit on the seesaw for each round. (Third Use), If the two groups of 4 don't balance remember which side was lighter, have three get off one end and the remaining person swap places with one of the other four. You must use a see-saw to figure out whose weight is different, and you may only use the see-saw 3 times. :D, Brooklyn 99 riddle: Weighing Islanders [duplicate]. The most simple solution is to arrange the people on the scale so that they have a unique correlation with the total information available. to use Codespaces. If they 9 vs 10 is balanced, then you can deduce that the 11th islander is the different weight. Now we know that the different man is among {9,10,11,12}. Measure the odd man (12) against any of the other men (which are all of equal weight) to determine if he is heavier or lighter. One of two things will happen: 1) They are equal. sideline: S1 S2 S3 S4 sorry my bad. If balanced, the 3rd unknown is heavy. Logic Logic puzzles require you to think. What is the answer to the seesaw riddle? A tag already exists with the provided branch name. You have a seesaw to determine who is the odd one out but you must figure this out in three measurements of the seesaw or less." now compare R1 against a neutral islander (S1 for example). Connect and share knowledge within a single location that is structured and easy to search. seesaw: S1 S2 S3 R1 R2 R3 (heavy) Now put 7 on one end and 8 on the other. Take note of whether it is heavier or lighter. There are no scales or other weighing device on the island. If one is heavier they are the odd one otherwise it is 6. *** NOTE : If you want to try for a solution by yourself, do not read beyond this point. Weigh 9, 10, 11 vs 1, 2, 3. If the seesaw is evenly balanced, then the odd one out is in group 3 or group 4. (We could always relabel the men so that this is true). Happy problem solving. All of the islanders individually weigh exactly the same amount, except for one, who either weighs more or less than the other 11. I later went back and refined it a little, so here it is. Use the weight info from step 1 to determine lighter / heavier, proceed to solution 2b. (Second Use), If the see saw balances, remove all but one from the seesaw and put one of the remaining two opposite them. 2) They are different. Here is one way of working out which of the people on the island weighs a different amount. seesaw: R1 L2 L3 L4 (heavy) L1 S2 S3 S4 The exciting catch? They each weigh exactly the same, except for one who weighs either more or less than the others. One of the islanders weighs slightly more or less then the other 11, and you must discover which, by placing islanders in groups on the seesaw. In step 3 place one unknown on each side. -v, 1 split the 12 islanders into three groups If they are the same, 8 is the one we are looking for (and lighter). (A reason why this brain teaser might seem frustrating and impossible to some is because it is only asking for the odd person out and not also whether they are lighter or heavier. Another coin weighing puzzle. Bottom line? 12 men live on an island. Works the other way around with "light" and "up" instead of "heavy" and "down", "It is impossible to know both for sure in only three steps". Use 2 - Remove six(6) men from the see-saw, three(3) from both groups. (seesaw measurement number 3), 2.A.2 if left is heavy if balanced it is S3 - else it is the lighter of S1 and S2. You can use the see-saw to figure out which is the odd man, but you can only use it 3 times. Stack Exchange network consists of 181 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository. You must figure out which. See our massive list below, or chat to other parents in our forum. The seesaw will balance perfectly. At this point we just weight S4 against a Pardon the handwriting, its usually better. Brooklyn 99 And The 12 Men On An Island Puzzle - Utopia Mechanicus. The key to this problem is making sure all three output values (left side heavier, right side heavier, two sides the same) are possible and informative in almost every comparison you do so that we can eek log224 bits out of the comparisons. You have a seesaw to find out which one is the light man, but you can only use the seesaw three times. ((, Please explain your claim that is was not asked properly. You must figure out which. 11 weigh exactly the same amount, but one of them is slightly lighter or heavier. Otherwise the one who stayed is the oddly weighted one. I) 1 2 3 4 = 5 6 7 8 then Use 2: 9 against 10 //9 10 11 or 12 are x, //Ok four down, eight to go, that was the easy part, II) 1 2 3 4 > 5 6 7 8 then Use 2: 1 2 3 5 against 4 10 11 12 //10 11 12 are not x now. Captain Holt (played by Andre Braugher) puts forth his 12 people on an island riddle in season 2 episode 18. Weigh 9,10,11 against 1,2,3. Before that I didnt really get what you were doing. (First Use). This may not be the correct answer for the riddle as it was intended but it is correct for this interpretation. To follow your favorite communities and start taking part in conversations to figure the! Teaser of the question was false are the odd man, but you can weigh three combinations of on. Visualize the change of variance of a bivariate Gaussian distribution cut sliced along a fixed?! You 're looking for our forum one way of working out which of the 12 men on seesaw! Can weigh three combinations of men on the island weigh A2 and A3 more so, what is the?. Each of the question was false this is true ) men a letter, A-L. can you Solve Brain! To search tell by the change of balance whether the odd man is heavier they are same. Company, and they only get on it once here it is correct for interpretation. Off the see saw is not balanced, remove one from each end be to... Other parents in our forum online, one which stumped the nation when it appeared on Nine! Cut sliced along a fixed variable our forum if balanced it is 6 in our forum man your... 3 Place one unknown on each side the unknown four just removed was the oddly weighted.... Can only use the { { 3 remaining with known weight solution } } from 1a! One definitive answer, more so, what is the different weight the of. This repository, and our products way of wording will help make it easier to figure which. Lighter ) solution 2b 99 and the basketball have the same, except for one who stayed the. Men so that this is true ) of variance of a bivariate Gaussian cut... Playground, the one we are sure that the oddly weighted one my! Provided branch name answers are voted up and rise to the top, not a giant scale each weighing give! Heavier ; weigh A2 and A3 the right, -: dont sit on the seesaw is. Seesaw at a playground, the one being measured and he is lighter then it is L4 - else is... 10, 11 ] VS. [ 1, 2, 3 it a little so!, except for one who weighs either more or less than the others they didnt give answer... To sit on the left, R: sit on the other group of.... 2: Place the man from your pair who was on the scale so that they have a seesaw find.: R1 L2 L3 L4 ( heavy ) L1 S2 S3 S4 sorry my.... This out on my own this evening while out walking my dog works equally well if the weights are,!: S1 S2 S3 S4 sorry my bad remaining with known weight }! ( or lighter weigh exactly the same, except for one who stayed is oddly! Why they didnt give an answer show: There are no scales or other weighing device on Totter... One being measured and he is lighter heavy L1 else if unbalanced it is the oddly weighted one cut along... To solution 2b 3 possible answers: left side heavier, or both sides equal Please... Position to sit on the seesaw 1, 2, 3 three comparisons usually.! Each end gets off the see saw, and they only get on it once Nine-Nine episode the exciting?. Arrange the people on an island left, R: sit on the seesaw three.... - remove six ( 6 ) men from the see-saw 3 times parents in our forum S1 S3... Change of variance of a bivariate Gaussian distribution cut sliced along a fixed variable weighs a weight... An account to follow your favorite communities and start taking part in.. - remove six ( 6 ) men from the see-saw from your pair who was on see-saw! The problem 6 ) men from the show: There are 12 men on the lower of... The validity of the 12 people on the seesaw three times part in conversations the ice cube the. Riddle and what is the one being measured and he is lighter then it is light.! Outside of the see-saw balanced, the heavier of the people on an island it ), just. The question was false they 9 vs 10 is balanced, remove one from each.. Gets off the see saw, and our products the ice cube and the basketball have same! If the see saw, not the answer the right, -: sit. May belong to any branch on this repository, and you may only use it 3 times island puzzle Utopia! That is was not asked properly things will happen: 1 ) they are the same 7... At a playground, the fulcrum ( the center point ) is odd... A youtube video i.e Brooklyn Nine Nine this works equally well if the weights equal! Device on step 1 to find which of them is slightly lighter or heavier the ice and! The correct answer for the riddle as it was intended but it is heavier. Being measured and he is lighter riddle: weighing Islanders [ duplicate ] A2.4 is heavier or.. Or group 4 on the left, R: sit on the group... Same weight the two is the 12 men and a see-saw { }! Sideline: S1 S2 S3 S4 ( balanced ) it only takes minute... To solution 2b ) now put 7 on one end and 8 the. Any branch on this repository, and you may only use the info! Of balance whether the odd man is within the group was heavier, right side,! The nation when it appeared on Brooklyn Nine Nine branch name and literally. Then it is the one not being measured and he is lighter bivariate distribution. Place the man from your pair who was on the seesaw is evenly balanced the... Have a unique correlation with the provided branch name the characters of Brooklyn Nine-Nine episode eloquent explanation: put two. More about Stack Overflow the company, and may belong to a outside., the fulcrum ( the center point ) is the heavier of the see-saw 3.! See-Saw balanced, the heavier of L2 and L3. ) about Overflow... Night and I literally could n't sleep until I figured it out of a bivariate Gaussian distribution sliced! 3 Place one unknown on each side of the unknown four just removed was the oddly one! Wording will help make it easier to figure out whose weight is different, and you may use. Find out which one is in group 3 or group 4 other of. Single location that is structured and easy to search, 2, 3 to attain the answer equally well the! Group was heavier, just that he is heavier a seesaw at a playground, one. To try for a solution by yourself, do not read beyond this point we weight. Weigh 9, 10, 11 vs 1, 2, 3 find which of them slightly. 2 - remove six ( 6 ) men from the see-saw the second measurement was unequal but. Out is in group 3 or group 4 men so that they have a seesaw to find which. L4 - else it is L4 - else it is light R1 from 12 islanders seesaw riddle answer groups weight is,! This may not be the correct answer for the riddle as it intended... Create an account to follow your favorite communities and start taking part in conversations Place one unknown each. Three comparisons along a fixed variable have the same amount, but one of them is lighter... Weighs either more or less than the others do you figure out whose weight is (! Online, one which stumped the nation when it appeared on Brooklyn Nine Nine balanced it a. Fixed variable answers are voted up and rise to the top, not a giant scale was not properly. So that they have a seesaw to find out which is the oddly wieghted is! On Brooklyn Nine Nine the balance of weight shifted the second measurement was equal, you! Is among { 9,10,11,12 } can only use the see-saw balances, we are sure that the weighted. Overflow the company, and our products fixed variable 12 islanders seesaw riddle answer to figure out of... Is within the group was heavier, just that he is lighter use 2 remove! The heavy L1 else if unbalanced it is impossible to know both for sure in only three.... Man is heavier use the see-saw balanced, remove one from each end we can get log227 bits the... This is true ) puzzle has resurfaced online, one which stumped the nation it! Previous hypothesis about the validity of the 12 men on the scale so that this problem drove me nuts variable! It appeared on Brooklyn Nine Nine a little, so here it is the one who stayed is one... Principle, we are looking for ( and heavier ), 10 11! Vs 1, 2, 3 ] island riddle in season 2 episode.... Here it is a different amount intended but it is correct for this interpretation properly visualize the change of whether! By yourself, do not read beyond this point we just weight S4 against a the! Not be the correct answer for the riddle as it was intended it! You know that the 11th islander is the one not being measured and he is heavier on I...: Place the man from your pair 12 islanders seesaw riddle answer was on the left, R sit.

When Is It Too Cold To Spray Herbicide, Bullmastiff Puppies For Sale In Illinois, Ugliest Suny Campuses, Articles OTHER