1000 logicians standing in a circle are blindfolded and a hat of either black or white color is placed on each person's head. The blindfolds are then removed and each person can now see everybody's hat color but his own. After exactly one minute, they all have to simultaneously guess their own h...

My apologies is this is not the right place for this question, please advise if it needs to be moved or deleted. So my city has an art installation of some very tall Dr.Suess style flowers. These flowers have barcodes that runs down the length of the stalk and I am looking for ideas on how to c...

A few days ago I picked up a solved Rubik's Cube that I had abandoned due to forgetting how to solve it, and started turning the faces to make nice patterns. A few minutes later, I'd made one - each face contained a P-pentomino in one colour and an L-tetromino in another: i.e. it looked like a ro...

Create all numbers 1 - 100 using equations made up of 1,9,6,8. Rules: Use all four digits exactly once Allowed operations: +, -, x, ÷, ! (factorial), exponentiation, square root. Parentheses and grouping (e.g. "21") are also allowed. Squaring can only be used in the number order with the numbe...

Currently on BBC Radio 1, one of the presenters is stuck in an escape room, and needs the listeners' help to break out. One of the puzzles is the following: Can the PSE community help? You can watch the livestream of the escape room here: https://www.bbc.co.uk/events/ezzcd4/live/cfz6v2

You are playing World of Warcraft which is well known an old MMORPG game. You are in arena where you play against another player. You are a mage and the opponent is a rogue which can hide while moving until a spell hits on him. (so it is 1v1, Rogue VS Mage) Rogue is a stubborn player and he jus...

I love cats! And I love browsing cat pictures! :3 I stumbled on a webpage that shows random cat pictures every time I refresh the page. (For example, this site.) It has a database of $N$ cats and will pick any random picture in probability of $\frac{1}{N}$. I really enjoyed it. Up ...

There are 'X' number of trees and 'Y' number birds. If 1 bird sits on each tree then 1 BIRD will be left. If 2 birds sits on each tree then 1 TREE will be left. What is number of trees(X) and birds(Y)?

A company of 50 employees, each of whom use the bathroom twice a day for 10 minutes at a time, at random times between 9am and 5pm (8 hours), has a bathroom which consists of 2 cubicles. If an employee goes to use the bathroom and both cubicles are occupied, they wait exactly 15 minutes and ...

Solve the clues and fit the answers into the grid so that each of the coloured squares contains exactly four different letters. Sahara desert capitals of historically African region in Germany (4) Fifth Element: Besson's first and last is full of romance gold (5) Second detecti...

Riddle: It's 7:00 AM. You are asleep and there is a sudden knock on the door. Behind the door are your parents who came to have breakfast. In your fridge are bread, milk (pasteurized), juice, and a jar of jam.

I need help in solving this sequence: ?, 36, 36, 18, 16, 14, ? i've tried to notice a pattern and saw that 7*2=14 8*2=16, 9×2=18 18×2=36 but after 9x2 the sequence doesn't make sense,i've also Tried to see the numbers as a sum of their numers so 1+4=5 1+6=7 1+8=9 3+6=9 3+6=9 I suppose that aft...