This is part 65 of the puzzle series Around the World in Many Days. Each part is solvable on its own. ”It’s not the size of the crossword that counts.” – unknown Dear Puzzling, Today I have dived into the crystal clear waters of a tropical island group known for its diverse flora and fauna. I ...

Consider an 8x8 grid made up of 64 unit squares. The goal is to color the 64 squares red or blue so that the following two constraints are satisfied: ROWS: For every pair of adjacent rows, exactly half the squares in the upper row must match the color of the square in the corresponding position ...

The clues below aren't hard to solve, but can you tell me what 3-word phrase that's hidden? One of me is used to hit the ball hoping to get a home run afterall. (3) One of me is often cubic shaped and used to store things, sometimes mail it brings. (2) One of me is used to see how fast people ...

Upon entering a (very) large room, you are faced with an infinite line of cardboard boxes that are labeled, in order, by the nonnegative integers. In one of these boxes, a cat is hiding, but you do not know which one. Your task is to find the cat in this setup. To do that, you and the cat take tu...

I have an old laptop and I have some files on it I need but I forgot the password, it's a 4 digit code and the only hint given to me is "Macaroni". Please help!

Can someone help with a problem from my math textbook? This is the problem I'm stuck on: I don't really get how these kinds of problems work. I think they want me to find the width of the rectangle? But how would I do that? Now before you complain "This is the wrong site for solving math textboo...

A new mathematical approach to quantum physics via graphs was found recently, see this paper for more details. It particular, it refers to papers by Anton Zeilinger, a Nobel laureate in physics of 2022. The approach is very promising. One of the authors, Mario Krenn, wrote to me: I would propose...

A Venn diagram consists of a set of partially overlapping shapes on a plane, arranged in a particular way: for any particular labelling of each of the shapes as "inside" or "outside", it is possible to find a point that is inside all the "inside" shapes and outside all the "outside" shapes. The m...

Life isn't merely a collection of legendary moments, but those are the ones we cherish: the great milestones of humanity, the sparks of creativity, curiosity, exploration, and endurance. Even when no one else was there to witness these events, they shared one common trait: the timing was perfect....