logic grid - Baggage Mishap Puzzle

This is a puzzle from Braingle:Savannah got distracted when her shuttle arrived at Earth Central Airport. Now she's at Lost & Found with four other travelers all waiting to retrieve one lost piece of luggage of a different color (black, blue, green, red or yellow.) While filling out their baggage retrieval paperwork, they discovered an amazing coincidence. Each person had the last name of one other person's nationality and another's destination country (America, England, France, Panama or Zambia). Nobody had the same last name, nationality ...Read more

Interesting logic puzzle grid problem

Here is a very challenging logic deduction puzzleThis is not for a graded homework assignment, however it was given to me by a professor for fun. If you post an answer, please discuss how you reached your solution. The questions are very interesting and quite challenging!I've posted my progress in an answer below....Read more

14 crosses in a 6 by 6 grid

Can you put 14 crosses in a 6 by 6 grid so that there are an even number of crosses on each row and column?An elementary school teacher asked me for help with this. Below is a photo of the book they are using. The text is in Swedish and it says "Draw 14 crosses in the grid so that there is an even number of crosses in each horizontal and vertical row". I already gave my answer to the teacher, so why don't you try to solve it!...Read more

logic grid - How many clues are required to ensure Einstein's Puzzle is solvable?

I used to play Einstein's puzzles a lot when I was younger, and very quickly learned to assess quite rapidly whether I thought a puzzle would be a quick solve or more time-consuming, but I never worked out the detail on how many clues are required.Is there a mathematical description of the minimum number of clues required to guarantee a solve, beyond which all further clues are unneeded but make life easier?...Read more

logic grid - How do I reduce a negative hint with multiple possibilities?

This is a hypothetical question about grid-style logic puzzles. I know that when there are positive clues, you reduce the puzzle by eliminating possibilities that don't come in pairs; for example, if the clue is "The one who likes rain plays the flute", you remove all flutes that don't line up in the same columns with rain and all the rain that doesn't line up with a flute. But what about negative clues, such as "Ryan doesn't eat steak" with multiple possibilities for each? If either Ryan or steak is already known, I can eliminate the other fro...Read more

logic grid - Megan and the rambling reshuffle

When I met Megan the other day in Starpounds, she was not her usual calm self."Goodness, what a shake-up! Everyone shifted from one job to another...""The Cabinet reshuffle?""Blithering ramblers!" she replied, a bit annoyed."Yes, those politicians can go on a bit, sometimes.""No, no. The Rambling Club. In Blithering." Blithering's a village just outside the city. "They had their AGM last week. Andy's taken over from Phil as chairman, but not only that -- nobody's got the same post as before.""Nice to have some new blood on the committee.""It wo...Read more

Grid based color changing puzzle

I am trying to identify the minigame used in the game Fontanero (the code for it is here). It consists of a 3x3 grid of squares, and each square is red or green. You can click on a square to invert the color of every square in the row and column of the square you clicked on. The goal of the game is to turn all of the squares a certain color. For example, if the board started like this: --- --- ---| r | g | r | --- --- ---| g | g | g | --- --- ---| r | g | r | --- --- ---and you clicked on the top left square, it would become this: --- --- -...Read more

Equivalent Grids

The two grids below are essentially equivalent. A specific color belongs to a specific catagory (four solid colors). Exception is the center box with 2 colors. Should be easy to fill out all the boxes with "?"...Read more