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  1. I assume that they also all get the clue that their numbers are unique.
    2 points
  2. With a tip of the hat to @BMAD for his interesting puzzle. For your amusement, here's an interesting spin on this genre: One night you encounter a two-hour traffic delay due to an accident (the tow truck had difficulty clearing the road.) So, for a time interval 13 of two hours you were constrained to travel at 0 mph. You called home and said, sorry dear, but I'll be two hours late getting home. The next night, for some unimaginable reason, you were also constrained to travel part of the way at 0 mph, this time for a distance of one inch. What do you say now when you call home?
    2 points
  3. In our circles you may find A laugh, a wink, a grin But pressure us we'll likely snap And send away our kin. We don't do much, we go to pot Such simple ones are we But with your hand we take command Or from you we will flee.
    2 points
  4. I’m the acrobat at your command, Give me a turn, or put me on the stand. I’m the sentinel, doorman you need, Give me a go, a go-ahead from me. Hit me, poke me, nail me in your wake, Without my flips, weak knees would quake. I live in one state and travel to another, Sunny side up or fumble in the other.
    1 point
  5. It looks like you're taking the first letter and essentially rotating it through the different positions while the other letters remain in the same order. I noticed that all the possible permutations begin with two letters that were next to each other in the original sequence (or in the first and last spot). For example, I don't think you can get a sequence starting with AC. So this does not seem to hold up.
    1 point
  6. An oldie but a goody (IMO): ****************************** Five-walled open house Shut my door and make it four. I know exactly who you are, Where you sleep, friends you keep. A loyal soldier out on tour I take my leaves overseas. So pin the gold upon my breast, Give me orders crossing borders.
    1 point
  7. Wait a minute, wait a minute, Mr
    1 point
  8. Though seldom seen, I'm world renowned Ever in flight above the ground. Teeth chewing, gnashing in time gnawing on knots, shunning the find. My hands at the ready, arms at the stay Heart like the sun, burning away. Ears like a rabbit's, pinned to the side-- Listening close, far and wide.
    1 point
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  10. 1 point
  11. The answer should be 25. My "proof" is a brute force programming solution. I have a psuedocode c++ bruteforce solution. I can give the full version if requested. It takes a few seconds to brute force all possible paths. This might count as a proof, depending on if you trust the computer to be reliable. Basically what it does is it generates all possible paths, and then prunes as it goes along so the program dosen't take basically forever, or 6^27 moves. Now a proof will involve some theorems in graph theory, which I don't yet know all that well. Assume the XYZ plane void recursive_dumb_solution( A 3D cube,Position of X, Y, and Z of current spot,direction it went twice ago, direction it went to get here){ if traveled along a direction twice in a row, return to the above function. else if( x<0 || x > 2 || y < 0 || y > 2 || z < 0 || z > 2) AKA if it exited the cube, return. else if(cube[x][y][z] == 1) AKA if visited spot already visited, then return. else{ //mark the current position of the cube as visited. cube[x][y][z] = 1; /////Moves in every direction possible. recursive_dumb_solution(cube, x+1, y, z, length+1,'x',prev_dir); recursive_dumb_solution(cube, x-1, y, z, length+1,'x',prev_dir); recursive_dumb_solution(cube, x, y+1, z, length+1,'y',prev_dir); recursive_dumb_solution(cube, x, y-1, z, length+1,'y',prev_dir); recursive_dumb_solution(cube, x, y, z+1, length+1,'z',prev_dir); recursive_dumb_solution(cube, x, y, z-1, length+1,'z',prev_dir); cube[x][y][z] = 0; return; } }
    1 point
  12. What is the answer of (x-a)(x-b)...(x-z)? The solution is contained in the video below https://youtu.be/CnHBE4SbRRs
    1 point
  13. Greetings, my name is Cody and I am new here in this forum. Nice meeting you all. Although I have never heard of it, I am actually quite curious about what it is!
    1 point
  14. . What is the value of x If 1/2, 2/3, 3/4, 4/5, 5/6, 6/7, 7/8, 8/9, 9/10 then x/1000? x = 500,000 2. If 4 and 2= 26, 8 and 1 = 79 and 6 and 5 = 111. Then, what is 7and3?...410 3. What 3 positive numbers give the same result when multiplied and added together? 2 mis interpreted the Q 1,2,3 is correct 4. What number do you get when you multiply all of the numbers on a telephone's number pad? zero 5. Here is a light switch. Note the order of the positions. If the light is now at medium and it is switched 3922 times what will be the position of the switch? medium I assumed in the absence of additional info there were 3 positions . i.e low , med , high. any even number of flips will put the sw back on med 6. Can you arrange four nines to make it equal to 100. 99 9/9 8. If 1/2 of 5 is 3, then what is 1/3 of 10? 3.67 I envisioned 1/2 of 5 = 2 1/2 + 1/2 = 3; therefore 1/3 of 10 = 3.33 + 1/3 =3.367 9. 100 students entered college. 55 of them chose music. 44 of them chose sports. 20 of them chose both. How many of them chose neither music nor sports? 21 10. Four friends are going to a concert. When they arrive, there are only five seats together left in the theater. The manager will let all four friends in for free if one of them can tell her how many different seating arrangements are possible for four people with five empty seats. 120 5 seats taken 4 at a time 5 ! All four are let in free. Could you have given the correct answer? 120 5 seats taken 4 at a time 5 ! 12. At six o’clock the wall clock struck 6 times. Checking with my watch, I noticed that the time between the first and last strokes was 30 seconds. How long will the clock take to strike 12 at midnight? 5 hrs 59 1/2 minutes 13. There are several books on a bookshelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf? 9 14. John has been hired to paint the numbers 1 through 100 on 100 apartments. my bad 20 How many times he has to paint 8? 20 15. You have two books. One of them is upside-down and the other is rotated so the top of the book is facing you. What is the sum of the first page in each book? 1 +1 16. There is a certain club which is for men only. There are 600 men who belong to this club and 5% of these men wear one earring. Of the other 95% membership, half wear two earrings and the other half wear none. How many earrings are being worn in this club? 600 17. Does a pound of gold or a pound of feathers weight more? feathers 18. There is a chain nailed to the wall. The chain is 10 feet long and the center of the chain dips down 5 feet from where each side of the chain is nailed to the wall. How far are the 2 ends of chain from each other? on the same nail 19.Little Johnny is walking home. He has $300 he has to bring home to his mom. While he is walking a man stops him and gives him a chance to double his money. The man says "I'll give you $600 if you can roll 1 die and get a 4 or above, you can roll 2 dice and get a 5 or 6 on at least one of them, or you can roll 3 dice and get a 6 on at least on die. If you don't I get your $300." What does Johnny do to have the best chance of getting home with the money? keep on walking 20. If you have 6 women and 2 friends, how many women do each of your friends get if the friends are two of the 6 women;i.e. women themselves , then each is entitled to herself, or one each/ If the two friends are male then no women.
    1 point
  15. . What is the value of x If 1/2, 2/3, 3/4, 4/5, 5/6, 6/7, 7/8, 8/9, 9/10 then x/1000? x = 500,000 2. If 4 and 2= 26, 8 and 1 = 79 and 6 and 5 = 111. Then, what is 7and3?...410 3. What 3 positive numbers give the same result when multiplied and added together? 2 4. What number do you get when you multiply all of the numbers on a telephone's number pad? zero 5. Here is a light switch. Note the order of the positions. If the light is now at medium and it is switched 3922 times what will be the position of the switch? medium 6. Can you arrange four nines to make it equal to 100. 99 9/9 8. If 1/2 of 5 is 3, then what is 1/3 of 10? 3.67 9. 100 students entered college. 55 of them chose music. 44 of them chose sports. 20 of them chose both. How many of them chose neither music nor sports? 21 10. Four friends are going to a concert. When they arrive, there are only five seats together left in the theater. The manager will let all four friends in for free if one of them can tell her how many different seating arrangements are possible for four people with five empty seats. 240 All four are let in free. Could you have given the correct answer? 240 12. At six o’clock the wall clock struck 6 times. Checking with my watch, I noticed that the time between the first and last strokes was 30 seconds. How long will the clock take to strike 12 at midnight? 5 hrs 59 1/2 minutes 13. There are several books on a bookshelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf? 9 14. John has been hired to paint the numbers 1 through 100 on 100 apartments. 11 How many times he has to paint 8? 11 15. You have two books. One of them is upside-down and the other is rotated so the top of the book is facing you. What is the sum of the first page in each book? 1 +1 16. There is a certain club which is for men only. There are 600 men who belong to this club and 5% of these men wear one earring. Of the other 95% membership, half wear two earrings and the other half wear none. How many earrings are being worn in this club? 600 17. Does a pound of gold or a pound of feathers weight more? feathers 18. There is a chain nailed to the wall. The chain is 10 feet long and the center of the chain dips down 5 feet from where each side of the chain is nailed to the wall. How far are the 2 ends of chain from each other? on the same nail 19.Little Johnny is walking home. He has $300 he has to bring home to his mom. While he is walking a man stops him and gives him a chance to double his money. The man says "I'll give you $600 if you can roll 1 die and get a 4 or above, you can roll 2 dice and get a 5 or 6 on at least one of them, or you can roll 3 dice and get a 6 on at least on die. If you don't I get your $300." What does Johnny do to have the best chance of getting home with the money? keep on walking 20. If you have 6 women and 2 friends, how many women do each of your friends get if the friends are two of the 6 women;i.e. women themselves , then each is entitled to herself, or one each/ If the two friends are male then no women.
    1 point
  16. Didn't watch the video - Will take too much data (for me)! Please show us the answers after everyone has had a go at them!
    1 point
  17. I watched the video, and overall liked it. Since you asked for feedback: with the video format, I think I would prefer to see the question and be told to pause to have time to think of the answer before it appears instead of having a set amount of time for each question, since with at least some of them you either know it or you don't right off the bat. As it is, I got a little annoyed waiting a minute for the answer if I already knew it. The other main comment is something DejMar sort of alluded to, that there are potentially multiple answers that would make sense for some of the riddles. In particular the second one, I also interpreted it as most likely being a gotcha where each number in the sequence is (n)/(n+1), so the final term x/1000 comes after 9/10 and should equal 10/11, meaning x = 10 x 1000 / 11. Only after realizing that it wouldn't be an integer did I decide that it probably wasn't what you intended to ask, so the answer should be the other thing I had in mind and be x = 999. With the light switch, when I saw it here I thought there must be three positions with something like "off" going to "medium", "medium" going either to "off" or to "high", and "high" going only to "medium" so there would be a unique answer -- after any even number of flips the switch must be back at "medium" -- whereas with the youtube version if you change directions during flipping you could either end up at the original position or 180 degrees away. For the question of painting 8s, I could have interpreted a couple of ways: you could argue that he would only paint 8 once (if it's referring to house number 8, or just the number 8 and not other numbers that happen to have 8 as a digit), that he would paint it 20 times (if you mean the total number of digits that are 8), or maybe even 19 times (if you mean the total number of houses with any 8 on them, although that's a less likely interpretation). DejMar commented on the ambiguity of whether the question with Little Johnny is talking about making it home with the original $300 dollars or the money that the man is offering, but I suppose that ambiguity needs to be present or else it wouldn't be much of a riddle. And the last question seems like it might be a bit offensive if asked to a woman. It might not be possible to make the questions entirely unambiguous, especially the question about Little Johnny since the ambiguity is what makes it a riddle in the first place, but sometimes simple things like saying "how many times does he have to paint the digit 8" can help make it unambiguous. In general, I would say to check for (and ask other people to check for) unintended ways that the questions might be interpreted.
    1 point
  18. A possible 3rd solution! If not. I'm giving up!
    1 point
  19. Two solutions. Maybe more?
    1 point
  20. It certainly should. It clearly fails a units check. Good catch.
    1 point
  21. The subtlety is…
    1 point
  22. Al, Bert, and Charlie competed in a track and field event in which points were awarded for 1st, 2nd, and 3rd, place only. At the end of the day, Al had accumulated 22 points, while Bert and Charlie each garnered only 9 points. No other competitor earned points. Bert was 1st in the shot put. Who finished 2nd in the javelin throw? This is a Gold star puzzle.
    1 point
  23. EDIT: For clarity, I use "number" to reference an individual digit. I use "sequence" to reference the string of numbers. EDIT2: Added spoiler tag.
    1 point
  24. Perhaps your question may hinge on the source of variability. Pistol has 5-7. In any skirmish, is the choice between 5, 6, 7 made by the program randomly? Or does it depend upon distance to target? Or visibility ( like heavy, light or no fog)? And, as Pickett points out, damage radius is a key parameter of the Dupuy lethality index.
    1 point
  25. Another factor to possibly consider...
    1 point
  26. Fuzzy thoughts:
    1 point
  27. You are shown a pile of dimes all of which have one of two distinct weights differing by a small amount not detectable by feel. Forty eight dimes are separated from this pile and you are told of these forty eight, light ones are a dime a dozen (literally - i.e. 44 heavy dimes and 4 light dimes). Using a balance scale twice, find seven heavy dimes. EDIT: for clarification
    1 point
  28. 1 point
  29. Ten years ago I called attention to a number that when divided by a single integer p it left a remainder of p-1. (Help, a remainder is chasing me) Here is a chance to construct a nine-digit number, a permutation of { 1 2 3 4 5 6 7 8 9 } that has no remainders, sort of. The task is to permute { 1 2 3 4 5 6 7 8 9 } to create a number whose first n digits is a multiple of n for any single-digit n. For example, consider 123654987. Its first 2 digits (12) are divisible by 2. It's first 5 digits (12365) are divisible by 5. However this is not a solution, since 1236549 is not a multiple of 7.
    1 point
  30. @flamebirde because Molly was playing off of the word easy, which is a popular Commodores song. No other reason
    1 point
  31. Assuming N people, the last standing (S) is given by: S=2*(N-2^m)+1, where m=floor[ln(N)].
    1 point
  32. Doesn't look like people get many responses in this section but I will introduce myself anyway. I'm a 36-year-old mom. I used to be smart, a long time ago. Was in the gifted program throughout grade school. Battled severe psychological problems starting in high school and am still battling them today. My grades in high school and college were pretty bad and I dropped out of pre-med. My younger sisters (who were not "gifted") have achieved much more academically and professionally than I have. Which is fine, because I like my life. But, sometimes I miss people telling me I'm smart! SO, I have started playing around with Mensa-type puzzles in an attempt to stretch my brain. I'm not having a lot of luck so far-- which is why I'm here.
    1 point
  33. Agree. When I hit the send button, I realized my thinking was too simple. But instead of deleting my post (moderator privilege) I left it to take its licks.
    1 point
  34. I believe you replace the ? with digits.
    1 point
  35. I swear: 1) To strangle the next person who uses 'suicide' as a verb. 2) That if I offended or hurt you in any way, I didn't mean it. 3) That I'll stop procrastinating. Tomorrow. Add whatever you swear.
    1 point
  36. Excellent riddle Plasmid. Those types are my favorite. Give yourself a 5 star vote and make it official. BTW . . . what's the "vote" thing for?
    1 point
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