Letters from Gladys are geography-themed standalone crosswords. Each puzzle has five thematic answers, which are places, sights or landmarks in or around a certain location (in this case, a city). Each thematic answer is notable enough to have its own article in the English Wikipedia, although n...

Two points are randomly chosen inside a circle. Is it always possible to draw a straight line through each point, such that they subdivide the circle into 3 regions of equal area?

Just practicing for an exam and I am a little stuck on some of the practice questions with the matrix puzzles below (total 8 puzzles): Question #1 Question #2 Question #3 Question #4 Question #5 Question #6 Question #7 Question #8

Having trouble figuring out these 5 pretty challenging matrix puzzles below: Question #1 Question #2 Question #3 Question #4 Question #5

A lonely chess knight stands on a cell somewhere in the first row of a 3x13 board, and elsewhere there is a castle. The knight takes a tour of all the remaining 25 cells of the board, missing just the cell where the castle stands. Where is the castle?

MIT's Baker House has a tradition of dropping an irreparable piano six floors every Drop Day, the last day one can drop a class without penalty (the 2022 date is 19 April). This year, in order to prevent damage to the asphalt, you have been asked to erect a net to catch the piano as a hack. Being...

This trick just isn't adding up for me: Take any whole number, Subtract a shorter whole number from it, Reverse what's left, then add 10 to it. You will find, for any number you've picked, your answer will match it! How can that be possible?

Let's have an orthogonal GRID where the individual squares have an area of 1cm$^2$. Let's join the the vertices of the squares A,B,C,D,E and A,H,G,F,E. The areas of the polygons ABCDE and AHGFE are equal because the polygons have the two pairs of sides equal and one side AE common. Now let's jo...

In Peter’s home bathroom, there was a standard shower stall with everything working in a conventional fashion. Then Peter used some simple plumbing tools, and some ordinary, low-cost plumbing parts to make a modification. The next day, Peter took a shower first while Pam waited her turn. Peter fi...

I can't figure out how to decode it and everything I try for it doesn't work: "Qhr nhrq lrvhf fs uoulfbye. Ln oenlos fs. Eedfiy. V mhuk... tuaw'm qhr pdmpwbrg: blreiefb"