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Everything posted by jasen

  1. after a week long journey abroad, now I'm active again. After thinking again, and using the clue harrey give us (scisors, pen, and paper), Yes it is possible to prove it without computer, but it takes many steps.
  2. each number must be an unique number or not?
  3. After rethinking this, I understand the doubter opinion. We have to avoid using "first bullet fastest" Although first bullet is not the fastest, it it still possible that the first bullet escape 1 4 2 3 -> in this arrangement 3 (first bullet) is not the fastest, but it escape. ----- we better explain it in another way. with n bullets, if the fastest bullet is not the first, there is (n-1)/n cases that we are sure there will be a collision. n-2 bullets will remains. an so on...
  4. OK, if there is crescent moon outside, this is one of the answers.
  5. The interesting fact is : Whatever number of bullets fired, the highest probability is 2 bullets left.
  6. 8593, 8600, 8593, 8592, 8599, 8593, 8591, 8598
  7. Well, it's nighttime, so you shouldn't see the Sun. The Sun is a star indeed, and it didn't occur to me the moon is not a star. Supposedly you could deduce the cardinals from the hour and the moon position? In the night you can't use sun as guidance. Unfortunately no astronomer between the prisoners, nobody could deduce the cardinals from the hour and the moon position. You see arround, wheather there are tools you can use. But you only can find electric lamp, hanging photo, and the working clock. 1st clue : use component from the clock.
  8. you are a prisoner in a huge jail. All prisoner will be executed in the morning next day. Fortunately No guard there. Suddenly in midnight a prisoner can break his cell. and take all keys. But he will not free and let others escape with him, except there is someone can tell directions (south, east, north or west), because wrong directions means recaptured. Nobody can read star for directions. You see a clock on the wall ticking, and your execution time get closer. What should you do to know the right direction?
  9. This is a subject in cryptography A don't want to send his key to B. B also don't want to send his key to A. But they want to communicate in insecure Internet connection. So they have to use an encryption method which work like this. Only commutative encryption method can answer this problem.
  10. I have a solution it can be really stright, not just by add S in front
  11. fore case 2, I have run a computer simulation, which show that you should not bet.
  12. In creating a question in An IQ test, the creator must make sure that there is no double interpreatation to the question (the question can be answered differently) example if you ask : 1,2,.... a. 3 b. 4 c. 5 this is a bad question, because there is a double interpretation there you usually answer a.3 but b.4 is also correct, because : 20 = 1, 21 = 2, 22 = 4 so to avoid this, one of the correct answer must be removed from the question. ------- in the question above you may think the logic that I over is questionable. But it also acceptable, so if the question maker do not allow my logic, so he must prevent this kind of logic appear, so he must create another option that is also not a duplicate. but since my logic, and pavan logic come to one option, so this is still acceptable. So, if we have found a logic in an IQ test question, just use it.
  13. Right answer, but I'm sure some of us still wonder why.
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