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Pickett

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Posts posted by Pickett

  1. Month Codes

    in New Logic/Math Puzzles

    Posted · Edited by Pickett

    Spoiler

    Agree with 681...Next up would be:

    • September: 9919
    • October: 71015
    • November: 81114
    • December: 8124
    Spoiler

    The "code" is simply:

    • {NUMBER OF LETTERS IN NAME}
    • {ORDINAL NUMBER OF MONTH IN YEAR}
    • {ORDINAL NUMBER OF FIRST LETTER IN ALPHABET}

    For example, for "January", it is:

    • 7 letters long
    • First month in the year (1)
    • begins with "J" which is the 10th letter of the alphabet

    So January = 7 1 10

    Going with that, August would be 6 8 1

     

     

  2. Did you get more than me?

    in New Logic/Math Puzzles

    Posted · Edited by Pickett
    Misread original post.

    Spoiler

    B and C each have 1 piece...D has X pieces (where X>1), and A has 11-X pieces.

    Let's walk through this:

    We are starting with the assumption that everyone got at least one piece

    When A asked B if he had more and B said "no", the only way he could know that is if B only received one piece...Because with that, there is no way he could've had more than A...he could have had the SAME, but not MORE.

    So then B asked C the same, and the same logic applies. So B and C each had 1 piece.

    At this point we know B and C each had 1 piece, which means there are 11 pieces unaccounted for. D knows all of this information because of what he just heard, and as long as he has 2 or more, he knows he has more than C...and he would know exactly how many because A would have (11-D), which is why he can say his statement.

    If our original assumption is incorrect, and people were allowed to have 0, then B and C both had 0 as CaptainEd mentioned...although D would have at least 1, not 0, and A would have the rest.

     

  3. Submitted for your perusal

    in New Word Riddles

    Posted

    This is either sheer madness or complete brilliance. 

    It's a lot to read, and I've only briefly skimmed it because i don't know if I have that much time to dedicate to it, but I've definitely noticed a number things out of this that will start to relate each of the paragraphs and "poems" together as well as a number of random pieces of information. A few examples I found:

    • It ends with an Irish Blessing (although it is missing the final piece: "May God hold you in the palm of His hand.")
    • There is an entire section containing pieces of song lyrics (Lou Reed - Walk on the Wild Side, Leonard Cohen - The Future, Simon and Garfunkle - The sound of Silence, Schoolhouse Rock - Conjunction Junction, The Trashmen - Surfin Bird, Gorillaz - Empire Antz, Tom Petty and the Heartbreakers - Runnin' Down the Dream, etc)
    • There are repeated phrases or words that seem too coincidental across the paragraphs ("Four Seconds", "Military Bases", "Capital G God", etc)

    So, again, I'm not going to have time to spend digging into this, and i'm still not completely sure if it's actually worthwhile, but it definitely piques my interest and will be checking in on this one...

  5. Emoji based math puzzle - level easy!

    in New Logic/Math Puzzles

    Posted

    Spoiler

    These emoji math things are always the same...

    By equation 1: wink = 10
    By equation 2: devil = 5
    By equation 3: hearts = 7

    Now, with equation 4, you do have to make an assumption that the smiley behind the first winking is a second winking (likewise with the heart smiley) AND that the expectation of having 2 of them together means addition...but assuming those things, you have what Kapris said:

    (2*7)+5*(2*10)

    ...but the ANSWER to that is not 380, it is 114.

     

  6. Crystal Problem

    in New Logic/Math Puzzles

    Posted

    Isn't my answer above correct?

    Spoiler

    Isn't it just the tetrahedral numbers...the formula for the series is

    Sn = n(n+1)(n+2) / 6

    So, for n=1,000,000, you have ((1,000,000)(1,000,001)(1,000,002)) / 6 = 1,000,003,000,002,000,000 / 6 = 166,667,166,667,000,000

     

  9. Bisecting a triangle

    in New Logic/Math Puzzles

    Posted · Edited by Pickett
    It duplicated my response for some reason....

    I'll take a quick stab at it:

    Spoiler

    sqrt(2π) / 4 = ~0.62666

    The "obvious" first answer is sqrt(2) / 2 (bisect the 90 degree angle perpendicular to the hypotenuse)...But if we step back and look at it a different way: The current triangle has an area of 1/2...

    So, we simply need to make a cut that leaves two areas of 1/4 (not necessarily similar shapes). The shortest STRAIGHT cut would be the sqrt(2) / 2, but if we decide to make a curved cut, we can get it shorter. I'll try to describe it (can't add pictures right now)

    Choose one of the 45 degree angle points and center a circle there with radius r. Mark the points along the hypotenuse and adjacent leg at points to create a segment of a circle with a 45 degree angle and radius r. We know, then, that is exactly 1/8 of the area of the full circle. Since we are trying to get an area of 1/4, and we have 1/8 of a circle, the full area of the circle would be 2. so we can figure out the length of r by doing πr2=2. Leaving us with r = sqrt(2π) / π

    Given that, we need to find the length of just that arc of the circle...which is 1/8 of the perimeter. So we know P=πd...which leaves us with P=2*sqrt(2π). Divide it by 8, and you get sqrt(2π) / 4 as the length of the arc connecting your points...leaving 2 pieces of the triangle with areas of 1/4 each.

     

     

  13. Thinking of a Number

    in New Word Riddles

    Posted

    curious as to how obscure these are or even the pronunciation allowed for these. Here are some examples of what I would consider "valid", but probably not what you're looking for:

    Spoiler

    π/1 = "pi over one"

    1.1 = "one dot one"

    0.0 = "oh point oh"

    So it really comes down to what "words" or "interpretations" are allowed here? Are greek letters allowed? are "non-standard" pronunciations of digits allowed? What about mathematical symbols?

     

  14. Celebrity Interview

    in New Logic/Math Puzzles

    Posted · Edited by bonanova
    Coveted bonanova gold star

    Spoiler

    I'll go with "To be, or not to be..."

    Write it as a logical expression (in hex): 2B | !2B

    2B = 00101011... !2B = 11010100

    So 00101011 | 11010100 = 11111111 = FF

    Not sure if that's what you were going for, but it makes sense...

    bona_goldstar.gif

  15. Thinking of a Number

    in New Word Riddles

    Posted

    Spoiler

    If you count "y" (which in this case is a vowel): eighty-one

    But you didn't have "y" listed, so I'm guessing not...

     

    Spoiler

    If you count "y" (which in this case is a vowel): eighty-one

    But you didn't have "y" listed, so I'm guessing not...

     

    Spoiler

    If you count "y" (which in this case is a vowel): eighty-one

    But you didn't have "y" listed, so I'm guessing not...

     

  19. Dots, not hats...

    in New Logic/Math Puzzles

    Posted

    So bonanova's most recent puzzle, Another hat problem, reminds me of one of my favorite riddles that my dad always told me. It's very similar, but slightly different, and I don't think I've posted it before, so here it goes (he was a much better story teller than I, so pardon my narrative):

    A king put out a decree saying he will give his entire kingdom to the person who could solve all of his riddles, thereby proving to be the smartest person in the land. Obviously many showed up, but after all of the trials, only 3 people remained. The king told them to get some rest for tomorrow they would face their final challenge. Only one person would remain after it, the other two would be killed. That threat didn't dissuade them, and they all went to bed.

    When they woke up, they found themselves all in a room together. Any and all reflective surfaces were covered, and there were armed guards surrounding them. Before any of them could speak, the king told them their challenge:

    "While you were sleeping, we painted either a red dot or a blue dot on each of your foreheads. You are not allowed to speak or communicate with each other in any way shape or form. Anyone who does so will be killed immediately. Now, raise your hand if you see a blue dot on someone else's head."

    The three people looked at each other and all three raised their hands.

    "Good. Keep your hands raised. You may only lower your hand when you can tell me what color dot is on your own forehead. If you lower your hand and do not answer, you will be killed. if you answer incorrectly, you will be killed. If you answer correctly, you will gain all of my wealth, and the other two will be killed. Good luck."

    The three looked at each other...what seemed like hours went by with no one answering. You could see they were all straining themselves, trying to figure out how they could know what color dot they had. Their arms started getting tired...

    Finally, one of the men got a big smirk on his face. He did some final double checking of his logic and slowly lowered his hand.

    "The spot on my head is ... "

     

    Given that the man successfully answered the question, and it clearly wasn't a "guess", what color dot was on his head, and how did he know?

  20. Another hat problem

    in New Logic/Math Puzzles

    Posted

    Spoiler

    Long story short: Adam must have a red hat on.

    Let's start from Charlie's point of view:

    • If Adam and Bill both had the blue hats, then Charlie would IMMEDIATELY say "RED!" (since there are only 2 blue available).
      • If he does yell red immediately, then both Adam and Bill would know their hats are blue.
      • Because the OP says that only Adam knew the color, this scenario can be dismissed.
    • This means Charlie sees either one red/one blue hat or two red hats and therefore can't know what color his hat is.

    Now we move to Bill:

    • Because Charlie doesn't respond right away with "red", that tells Bill he and Adam couldn't both have blue hats.
    • So if Bill sees a blue hat on Adam, Bill would immediately say "red"...
      • If this happens, Adam should know based on the logic above that he has a blue hat on, and so he would say it
      • This would mean both Adam and Bill know their color, so this scenario is out as well.
    • So that means Bill must see a Red hat on Adam.

    So based on the above reasoning, the fact that both Charlie and Bill don't "know" the color of their hats immediately, tells Adam that he MUST have a RED hat on...otherwise, at least one other person would know what color they have.

     

  22. Integer equation?

    in New Logic/Math Puzzles

    Posted

    Spoiler

    x3 - y3 factors into (x - y)(x2 + xy + y2)

    Which means if there are any integer solutions, x - y would be an integer and be a factor of 217. There are only 4 factors of 217: 1, 7, 31, 217. We also know that x3 > y3, which means x > y. With that information, we can take a "brute force" method to find all possibilities, knowing that x - y must equal either 1, 7, 31, or 217. It would be something like this:

    Assume x - y = 1

    1. Solve for x: x = y + 1
    2. Substitute: 217 = (y + 1 - y)((y + 1)2 + (y + 1)y + y2) = 3y2 + 3y + 1
    3. Simplify: 216 = 3y2 + 3y...72 = y(y + 1)
    4. Solve for y: y=8 or y=-9
    5. Substitute and solve for x to find 2 solutions:
      x=9, y=8
      x=-8, y=-9

    Now just repeat for x - y = 7, 31, 217 to find all solutions (note: after going through this, I realized you could probably logically drop 31 and 217 from the list of possible values from the start)...but regardless, the remaining integer solutions are:
    x=1, y=-6
    x=6, y=-1

     

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