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  1. Past hour
  2. Take a guess

    Haha, that's kind of fun to wrap your head around...
  3. Today
  4. New math

    flamebirde - last 2 digits
  5. Same numbers of heads

    Think this one has been posted before. EDIT:
  6. Dividend please (on steroids)

    ??? there are 3 digits before green digits , but there are 4 subtraction different from all after
  7. Grabbing marbles

    You are wearing gloves while trying to retrieve the marbles contained in a bag. Because of the gloves, you're doing a pretty poor job of it. With each grab, you are only able to retrieve a random number of marbles, evenly distributed between 1 and n, the number of marbles currently in the bag. With 30 marbles initially in the bag, how many grabs do you expect to make in order to retrieve them all?
  8. Same numbers of heads

    Twenty coins lie on a table, with ten coins showing heads and the other ten showing tails. You are seated at the table, blindfolded and wearing gloves. You are tasked with creating two groups of coins, with each group showing the same numbers of heads (and tails) as the other group. You are only permitted to move or flip coins, and you are unable to determine their initial state. What's your plan?
  9. Staying dry in the rain

    For the purposes of this puzzle, consider our old friend Albert to have the shape of a rectangular paralellepiped (when he was born the doctor remarked to his mother, I don't explain them, ma'am I just deliver them) just meaning a solid having (six) rectangular sides. At a recent physical exam, Albert was found to be 2 meters tall, 1 meter wide and .20 meters thick (front to back.) He maintains his geometric rectitude by never leaning forward when he walks or runs. So anyway, Albert, alas, has found himself caught in a rainstorm that has 1000 raindrops / cubic meter that are falling at a constant speed of 10 meters / second, and he is 100 meters from his house. Just how fast should Albert run to his house so as to encounter as few raindrops as possible?
  10. New math

    I think.
  11. Take a guess

    If you chose to answer this question completely at random, what is the probability you will be correct? 25% 50% 0% 25%
  12. New math

  13. Yesterday
  14. New math

    If 5+3+2 = 151022 9+2+4 = 183652 8+6+3 = 482466 5+4+5 = 202541 Then 7+5+2 = ______ ?
  15. Dividend please (on steroids)

    It's an alternative representation to put the quotient to the right side. Here is the more familiar placement. The green (overlined) digits repeat forever. _________________ x x x x x x x x x x x x -------------- x x x x x x / x x x x x x x x x x x x x ----------- x x x x x x x x x x x x x ----------- x x x x x x x x x x x x x x ------------- x x x x x x x x x x x x x ------------- x x x x x x x x x x x x x x ------------- x x x x x x x x x x x x x x ------------- x x x x x x x x x x x x x x ------------- x x x x x x x x x x x x x x ------------- x x x x x x x x x x x x ----------- x x x x x x
  16. Dividend please (on steroids)

    I dont really understand the question, why there are seven red x, what is symbol ( in the middle of dividend.
  17. Last week
  18. Race Riddle

    It is! Nice solve.
  19. Code to the safe

    I see, I found the solution for 8 generals, confused by range() in Python. The distribution for 7 generals:
  20. Code to the safe

    I'm coming up with…
  21. Race Riddle

    Holy crap, this is a top tier riddle. I'm stealing this.
  22. Race Riddle

    Is it…
  23. Is it a factor?

    I think…
  24. Help Bob find Alice's P(x)$%^

    Hmmm… assuming n is known to Bob, my first thoughts…
  25. The answer should be plain to see

    Lol. That's what lead to one of the other guesses. Plain to see--> crystal clear. Crystal would be fancier drinking cups though. And I couldn't quite call it white.
  26. Code to the safe

    The hard part is to generate the lock numbers from the generals, the formulas are quite complicated: There is a way to cheat: Both programs give the same list: The distribution: The solution sure is not unique, various combinations are possible. Not talking about the possibility that the lock 1 has to be unlocked to unlock locks 2 and 3.
  27. Poisoned Wine

    Yup, you both got it! I'm gonna mark Thundercloud as best answer since he was first by a couple of hours, but Aiemdao's answer is just as good and the one I had in mind (although I'm fairly sure both methods are identical).
  28. Race Riddle

    Named for the first wherever you go Hundreds of cycles in column and row. Grouped into teams oft coloured the same. Hardly one in each will ever earn fame. The race will begin when ball touches ground Millions of cheers can be heard all around. You expect it to start when northern half cools, But location may often vary the rules. Too fast or too slow, not so much a race, As all are required to maintain one pace.
  29. Alice and Bob are playing the following game: Alice has a secret polynomial P(x) = a_0 + a_1 x + a_2 x^2 + … + a_n x^n, with non-negative integer coefficients a_0, a_1, …, a_n. At each turn, Bob picks an integer k and Alice tells Bob the value of P(k). Find, as a function of the degree n, the minimum number of turns Bob needs to completely determine Alice’s polynomial P(x).
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