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BMAD

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Everything posted by BMAD

  1. How would you make 30? 9+9+9+1+1 = 29 9+9+9+4 = 31
  2. In my country i decided to develop my own currency. Long tired of the decimal system, i decided to arbitrarily make a new currency system. From now on 121 coins make 1 Bmad bill. $121 one BMAD bills makes a hundred and so on. Also, i decided that All numbers within each system must be reached by no more than five bills/coins. In other words. If i want 119 cents, then five coins or less must be enough to reach that amount. If i want 120 cents, then i would use at most five coins too but it does not have to be the same five coins that made 119. So to reach any price amount under a hundred, i would need at most five bills and five coins. Three questions: 1. What is the fewest number of coins needed to make the above true? What would be their values? 2. How many one BMAD bills are needed to make a million?
  3. lol, yes. I mean 1 million, $1 coins. verify the solution
  4. At the end of a trial an eccentric judge sentenced the accused individual to some number of years in prison. However, the judge pointed out that this individual should 'select' the number of years to be served by himself! The judge placed 12 boxes on the circumference of a circle. Each box was numbered, the clockwise sequence of numbers on the boxes was, 7, 10, 1, 3, 6, 11, 8, 4, 5, 9, 0 and 2. The sentenced man was told that there was a number of coins in each box; again, the clockwise sequence o numbers of coins was 0, 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 12. The sentenced man should select a box and the number of coins in the box would determine the length of the sentence. However, before the man pointed to any box, he asked the judge whether he could get any additional information, namely, how many boxes had numbers which exactly matched the number of coins they contained? The judge replied that such information could not be disclosed, as it would allow him to determine teh empty box. The man thought a little and pointed to the empty box anyway! How did he know? Which box did he point to?
  5. One million dollar coins are thrown into two urns in the following manner: At the beginning of the process, each urn contains one coin. The remaining 999,998 coins are thrown in one by one. Each coin lands into one of the two urns with different probabilities. If at any stage of the process the first urn contains x coins and the second urn contains y coins, then the probabilities that the thrown coin will fall into the first or second urn are: x/(x+y) and y/(x+y) The question is: how much should you pay (in advance) for the contents of the urn that contains the smaller amount of coins?
  6. Now what about the bonus question?
  7. Nice point radio1. I guess the question would be, would the start of round 1 mean the end of round zero and hence the bartender would be told that the glasses are not all in the same orientation. or would the start of round 2 be the first time the bartender is informed. To me, in a practical sense, i would tell the bartender that i am mixing up four glasses and he will have to correctly orient them while blindfolded (telling him the rules of the game), so essentially, i am telling him at round zero that the glasses are not in the same orientation. But either way, you are right in that Plasmid's solution still works.
  8. these are all very fine and well-argued answers. We ask this question at our work because of the vagueness in terms and lack of clarity of what we want to quantify. We are interested in learning how our potential employees build their argument and how they support (or would support if they had to go look for the information). We get some wild and rather funny answers beyond the well-articulated ones above. But I will have to reserve these responses for the joke section
  9. I took the statement " Each glass is either right-side-up or up side down" to mean that all the glasses were all in the same orientation to start with. I thought it must have been there to emphasize that no glasses where placed on their sides, which would, of course, be stupid. But, that makes it too easy, I suppose. I haven't yet considered the case where of an arbitrary beginning setup. Thanks for pointing that out, phil. If all the glasses were already in the same orientation (all up or all down), the game would be over before it started.
  10. well done Phil. I was having a hard time visualizing what Superprismatic meant.
  11. I would like to see what you mean.
  12. The following game is played between a customer and a bartender. The customer places four glasses on a revolving tray, arranged in a circle. Each glass is either right-side-up or upside down. The bartender is blindfolded and cannot see which way the glasses are placed, but the goal is to turn all the glasses the same direction. In each round, the tray is spun, and the bartender is allowed to touch only two glasses, turning over either or both of them. But the bartender does not know the orientation when he touches his glasses. After each round, the bartender is told if all glasses are oriented the same and the game is over. What is the best strategy for the bartender? Is there a maximum number of moves, after which the bartender can be certain all the glasses are identically oriented?
  13. What is the radius of the smallest circle that can enclose all 52 non-overlapping cards of an ordinary deck of playing cards? And what is the configuration of the cards? Assume the smaller dimension of the cards is 5 and the larger is 7.
  14. We have two numbers that multiplied together to produce another number. All of the digits were replaced with E for the even numbers and O for the odd numbers, showing the following setup: O E E x E E E O E E E O E note the use of x as the operator of times. O O E E What was the original problem?
  15. A boy is late for school often. When approached by his teacher, he explained that it is not his fault. Then he provided some details. His father takes him from home to the bus stop every morning. The bus is supposed to leave at 8:00 am but the departure time is only approximate. The bus arrives at the stop anytime between 7:58 and 8:02 and immediately departs. The boy and his father try to arrive at the bus stop at 8:00 however due to variable traffic conditions they arrive anytime between 7:55 and 8:01. This is why the boy misses the bus so often. Can you determine how often the boy is late for school?
  16. Yes. Anza identified the easier method
  17. Suppose we have to build a road from city A to city B, but these cities are separated by a river (straight, consistent width). We would like to minimize the length of the road between these cities and the bridbe must be constructed perpendicular to the banks of the river. Where to build the bridge as to minimize the total length of the road? I know two different ways to solve this problem. Can you find both?
  18. There are four cities located on the vertices of a square. Your task is to design a network of roads such that (1) every city is connected with every other city, and (2) the total length of the roads is minimized. The roads can intersect each other.
  19. now what about the tesseract? Presume the same action were possible
  20. If the cube was laying flat you would be right. But hanging it by a vertex causes a different shape.
  21. Given globs of ham, bread, and cheese (in any shape), placed any way you like, Prove that with a knife there exists a way to bisect each of the ham, bread, and cheese. In other words, show that you can share it with a friend so that each of you can have the exact same amount of the three globs of food.
  22. Hang a cube from one of its vertices. Now, if you slice it horizontally through its center, what 2-d shape will the slice yield? What if you do this with a 4-dimensional cube, i.e., a tesseract? The slice will yield a 3-dimensional object--- what does it look like?
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