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  1. Yesterday
  2. The halfway glass

    You're right. I botched it. rodomac's wordless pics were in my mind, but they never made it to the keyboard.
  3. The halfway glass

    I know what you mean but I don't think it is worded it right
  4. Last week
  5. Simple classic puzzle on profit

    I've not heard this one...but I'll take a stab:
  6. Bill sold his motor scooter to Tom for $100. After driving it around for a few days Tom discovered it was in such a broken-down condition that he sold it back to Bill for $80. The next day Bill sold it to Herman for $90. What is Bill's total profit?
  7. You and two of your friends would like to know the average of all of your salaries. You are each self-conscious about the amount of money you make and will not tell one another your salaries. What can you do to figure out the average salary?
  8. The halfway glass

    You are in an empty room with a glass of water. The glass is a right cylinder that looks like it is about half-full, but you are unsure. What is the most accurate way, without spilling any water, to determine whether the glass is half-full, more than half-full, or less than half-full?
  9. Bronx vs brooklyn

    A man lives in Manhattan near a subway express station. He has two girlfriends, one in Brooklyn, one in the Bronx. To visit either girl he must take a train. To go to the one in Brooklyn, he takes a train on the downtown side of the platform, and to visit the one in the Bronx, he takes a train on the uptown side of the same platform. Since he likes both girls equally well, he simply takes the first train that comes along. In this way he lets chance determine whether he rides to the Bronx or to Brooklyn. The young man reaches the subway platform at a random moment each Saturday afternoon. Brooklyn and Bronx trains arrive at the station equally often--every ten minutes. Yet for some obscure reason, he finds himself spending most of his time with the girl in Brooklyn. In fact, on average, he goes there nine times out of ten. Why are the odds so heavily in favor of Brooklyn?
  10. Russian Roulette

    After the chamber is spun , the bullet can only occupy 6 positions .
  11. Truth in packaging

    As all three boxes were labelled incorrectly there will only be 2 ways of doing this. Say this is correct order 1. Nails 2. Nails and screws 3.screws No dearrangments will be 1.S 2.N 3.N&S And 1.N&S 2.S 3.N So we will get the actual arrangememt by doing either doing two swaps ( 1&2, 2&3) for dearrangement 1 or four swaps (1&2,2&3) again (1&2,2&3) for dearrangement 2. So after doing two swaps we can take an item from a box and check. If it turn outs to be the wrong one. Then make two swaps. And we will get the actual arrangememt.
  12. Earlier
  13. Could or could not

    This might be a 10 digit phone number or not? The area code might be 505 or might not? Who can solve this one and how did you do it?
  14. Segment a segment

    There is a solution. the problem can be solved by them either being parallel or not intersecting. Since this is proving challenging, lets just focus on the parallel situation for now. Maybe I will repost the question for not intersecting later.
  15. Segment a segment

    One more thing , does this problem have a solution? And is the line and line segment given intersecting , parallel or just inclined and not intersecting?
  16. Truly Kryptic

    This is not a new brain teaser but a game where you have to find the secret word in order to proceed to the next level. There are 50 levels and it's addictive: https://trulykryptic.com
  17. Find the missing numbers

    Yeap, this is the correct answer!
  18. Number Series

    Exactly, thanks for taking the time to check!
  19. Find the missing numbers

  20. Number Series

    These are my guesses:
  21. Who can go the lowest?

    Since the integer requirement, there haven't been any replies, so I'll go with an obvious, and not-likely-to-be-optimal one.
  22. Chess Board Puzzle

  23. Which are the missing numbers? (a) (b) (c) (d)
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