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  1. Yesterday
  2. Find the meaning of this graphic nonsense :P I can give hints if needed, but please don't reveal raw data from intermediate steps, even in spoiler boxes. When you have found a result, hash it using sha256: the first 8 characters of the hash are 190a7ba4, give me the next 8. Start here:
  3. Last week
  4. well but if you say there are 9 eggs in a dozen that could be left to human interpretation but if you were to say an inequality there are at least 9 eggs in a dozen but at max 12 eggs you could write it e=amount of eggs 8<e<12 so when talking about the months in general from the minimum maximumday you could write it d=amount of day minimum maximum 28<d<31
  5. Stefaan


    Consider the following sequence: 0 1 1.0 2 1.0.0 1.1 3 2.0 1.0.1 What is next in the sequence?
  6. I wish to point out a trivial mistake in my OP ... The value at position C10 (1223) and the one at J11 (1226) have inadvertently not been swapped before posting, So both these values are in their correct placings. This means that only 14 swaps need to be done. No extra cycles, all straightforward X ↔ Y (one exchange per number with another).
  7. Earlier
  8. For the bowl with 2 poisonous apples out of 5, and you have to eat 3, there are 3 possible ways to die: The first way to die is by eating 2 poisonous apples in a row. The first time there's a 2/5 chance to eat a poisonous apple, which reduces to a 1/4 chance to eat a second one. Multiply these two together: (2/5)*(1/4) = 10% Second way to die is if you eat one good apple and then two bad ones: (2/5) * (2/4) * (1/3) = 6.6% Third way to die is if you eat one bad one, then a good one, and then a bad one: (2/5) * (1/4) * (1/3) = 3.33% Add these probabilities together, 10% + 6.6% + 3.33% = (Basically) 20% This means that the chance of dying is 20%, so a 80% chance of survival. For the second bowl there is only one way to die, and that's if you eat 2 bad ones in a row: (3/5) * (2/4) = 30% So that means there's a 30% chance of death and a 70% chance of survival, respectively. I can't figure out how people get to it being 70% for both.
  9. I'm pretty sure this isn't optimal, but it's a start.
  10. This is a great example of a puzzle “where intuition might suggest wrong answer.” Thanks Bonanova, and shout out to Event Horizon for showing us the right answer!
  11. In each case is there a swap? Or are there longer cycles as well?
  12. Back again for those I've met, Can't remember, do not fret, Although I wear a different mask, I bring for you another task, If this be our first time meeting, Let me start here with a greeting, Hi, Riddle is my name, And who I am is the game, Riddle me this: I am somewhere to each, To all I am out of reach,One line on paper is all I need, On a map this won’t do indeed, Many will go beyond their own, And those that did shall have grown, What or Who am I ?- Now go forth and find the answer, Before I become a private dancer, I really don't know what to say, So I’ll inhale mosquito spray, Line 2 and 4 were just to rhyme, 4 o'clock will be the time, At which there is a winner, Who will have a chocolate dinner, May the Force live long and prosper!
  13. Hi, Here are the clues; 1- This is a champion. 2- Another family adopted him/her. 3- He/she made great commercial investments. 4- He/she became a national symbol with his/her accomplishments. 5- There's a movie about him/her 6- He/she didn't start to his/her career with his/her own name. It is an a real person. We don't know if still alive or not. The answer is not : Lance Armstrong Milkha Singh Babe Ruth Demetrius Jackson Who could this personality be?
  14. In the ten numerical sequences below, three numbers from each sequence have been moved to another sequence, i.e. 15 numbers have been swapped. Which 15 pairs of numbers should be exchanged to make each of the sequences follow a regular pattern? (A) 37, 85, 148, 232, 333, 442, 589, 744, 917, 1108, 1317, 1544 (B) 42, 84, 144, 219, 310, 417, 537, 679, 834, 1005, 1208, 1395 (C) 44, 95, 166, 253, 368, 493, 650, 821, 1012, 1223, 1454, 1705 (D) 70, 122, 189, 271, 366, 475, 598, 735, 890, 1051, 1230, 1423 (E) 123, 181, 252, 335, 430, 540, 656, 787, 930, 1085, 1283, 1431 (F) 149, 209, 280, 361, 452, 553, 691, 785, 916, 1057, 1192, 1369 (G) 160, 190, 220, 253, 288, 325, 364, 406, 448, 499, 540, 589 (H) 253, 320, 395, 478, 569, 666, 775, 886, 1013, 1144, 1252, 1430 (I) 257, 300, 351, 405, 465, 528, 595, 668, 741, 820, 903, 990 (J) 306, 371, 452, 519, 602, 664, 786, 887, 994, 1107, 1226, 1351 Example In the two sequences below, 48 and 52 should be swapped to make sense (A5 ↔ B4). (A) 20, 25, 32, 41, 48, 65. 80 (B) 15, 24, 35, 52, 63, 80, 99
  15. its simple she says you will eat him which then if shes wrong then he will eat him but that means shes right but if he dosen't eat him then he will eat him and so forth.
  16. Rearrange this equation make it true using only move of one tooth-stick. L+VIII=X
  17. bill


    Which way to your camp?
  18. Hi @CynPyn and welcome to the Den. Let's accept from this that Rmax is the unit diameter circle. Now imagine a rectangle with unit diameter (diagonal has length 1.) That can be made to fit into Rmax . The question is does every unit-diameter region into Rmax ?
  19. Hi everyone, I'm a newbie to the forum and I love a good brain teaser/riddle - can't wait to get to know everyone and get into some teasers! I found a little warm-up one on my travels that's quite good if you're just waking up in the mornings First time round it took me a good 15 minutes! https://www.myfavouritevouchercodes.co.uk/blog/new-brain-teaser-find-shopping-bag
  20. Here goes... Rmax must be a circle of diameter one. To prove this, assume it isn’t. Then all other possible diameters of Rmax must be one or shorter than one. If this is true, then Rmax can fit inside a circle of diameter one, which has greater area than Rmax. Therefore Rmax doesn’t enclose the maximum area. By contradiction then, Rmax must be a circle of diameter one. Not my cleanest proof, but I’m thrilled to be the first response.
  21. The diameter of a closed, topologically bounded region of the plane is the greatest distance between two points in the region. Example: the diameter of a rectangle is the length of its diagonal. Of all the regions whose diameter equals 1, one of them, call it Rmax, encloses the largest area. Can you prove, or disprove, that Rmax also encloses all other regions of diameter 1? That is, that all other regions of diameter 1 can be made to fit inside Rmax?
  22. Previously, Maiden’s boat could change its heading instantaneously. Ogre’s heading could change only by virtue of following a circular path along the shore at his current speed. His rotational speed was thus far from infinite, and perhaps that disadvantage was unfair. So in this final puzzle iteration we’ll limit the boat’s linear speed to be f times that of Ogre, as before, but now we’ll also limit the boat’s angular speed to be never greater than g times Ogre’s top angular speed. A moment’s thought tells us that unless g is greater than unity the boat’s best strategy is to run at full speed from the center to the shore, keeping its initial bearing, no matter where on the shore Ogre initially stands. That is, never to turn the boat. That sucks for Maiden (e.g., she loses if Ogre initially stands at the boat's initial heading) and it sucks as a puzzle. So we’ll say the boat can change heading faster than Ogre can. For clarity we’ll set g = 2. We’ll implement that limit by giving the boat’s motor three discrete settings that can be switched instantly an unlimited number of times: clockwise (CW), full speed ahead (FSA), and counterclockwise (CCW.) In the two turning modes the boat turns but maintains its position; in FSA mode it moves forward but does not turn. Boat’s path is thus a succession of arbitrarily short line segments joined at angles of Maiden's choosing, with the time cost of the angle depending on its size. If the boat starts in the middle of the lake, how large must f now be for Maiden to escape? Edit: Extra credit (tough): If Ogre's top speed is 1 lake-radius per minute, and Maiden chooses the boat's initial heading at the center, what's her shortest time safely to shore?
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