My brother is currently playing the game Songs of Skydale and ran into this puzzle. There's a sequence of 3 patterns in the top row and you have to figure out which of the options in the bottom row is the fourth. He guessed the correct answer but we still don't understand the solution. We tried m...

What is the least number of moves required to swap black and white queens? Queens move using standard chess rules - any number of empty cells vertically, horizontally or diagonally in a straight line. You do not need to alternate players. Here is a similar question for rooks: Swapping 3 rooks in...

There are 100 lightbulbs in a room, each with it’s own switch in the off position (all lightbulbs work and start off, no funny business). There are also 100 people numbered from 1 to 100 standing outside the room. Each person enters the room one at a time and flips the switches of certain lightbu...

You've heard of the change LEAD to GOLD by changing one letter at a time. A player has suggested another, and we're having a hard time with it. BITTER to SWEETS.

This is part 5 of the puzzle series. Part 1 is here. Dear Puzzling, This is my most remote destination so far. The views out here are breathtaking, although from what I hear this place is even more beautiful if visited at a different time of the year. Maybe I need to come back at some point! Tw...

I'm buying a home gym set up for my son (really!) and I want to know the fewest number of weight plates I need to buy to be able to go up in 5kg increments to 170kg. The bar weights 20kg and the weights are available in 25kg, 20kg, 15kg, 10kg, 5kg and 2.5kg. It is cheaper per kilogram to buy bi...

On the following chessboard every white square meets at least two red squares. Let's paint a new chessboard so that every white square meets exactly two red square. It is clearly possible from the following chessboard. But, too many squares were painted red. What is the minimal number of square...

I have hidden something from my nemesis Aufero inside other words. The rules are that I can only add one or more letters to a word inside that word (not at the beginning or end), I can only add a single string of letters, and both words must be valid. For example, I can turn actuate into accentua...

A warden wants to play a game with his prisoners. He tells them that they have to tell him the color of their own hats if they want to have dinner. note: The warden may be mean, but the prison has a good cook; everyone wants dinner. The rules of the game: 1 The prisoners get blindfolded, and posi...

Long time ago in Egypt, an old man died and left a herd of 41 camels to his three sons. According to his will, the oldest son should get 1/2 of the camels, the second son 1/3, and the youngest 1/7 of the herd. While the sons were wondering on how to follow these instructions, a wise man came on h...

Srinivasa Ramanujan was said to have answered this question almost immediately when brought to his attention by Prasanta Chandra Mahalanobis, taken from a December 1914 print of The Strand Magazine: He said the house of his friend was in a long street, numbered on this side one, two, three, and ...

I have an app that has different levels of sudoku puzzles and I'm trying to learn to solve Expert. The app I'm using has a hint function, but all it does is fill in the correct answer in a selected square. That doesn't tell me why that's the correct answer or how I should have known it's the co...