puzzles

  • A drunk man

    A drunk man stands with a cliff one step to his left. He takes steps randomly left and right. Each step has probability p of going left and probability q=1−p of going right. Each step is the same size. If allowed to randomly step indefinitely, what is the probability that the drunk falls off the…

  • 200+ riddles for kids

    200+ riddles for kids

    Got a clever kid? Try one of these riddles for kids. Some are tricky, some are funny and all will get their brains working! What is a riddle? A riddle is a fun type of brain teaser that exists as a question or statement to be solved.  It can be framed in a way that is misleading,…

  • Rock, Paper, Scissors

    Adam and Eve play rock-paper-scissors 10 times. You know that: Who wins? By how much? Riddle from: Popular Mechanics

  • Wrong Statements

    How many wrong statements are in the list above? Riddle from: Brilliant

  • Two Doors

    You wake up in an empty room with only 2 doors. Each door has a key-hole where you can peek through. Door A is guarded by a dragon that will incinerate anyone it sees. Door B is simply a hallway, with an odd ceiling, it’s the strongest magnifying glass on earth! It magnifies the sun…

  • Super Lottery

    What are your odds of winning a 100 million person lottery with these rules? You are one of 100 million people playing in a lottery. On each drawing there is exactly one winner. What is the probability that you will win at least once before someone (could be any one of the other players) wins…

  • 100 Prisoners

    Can you help the prisoners communicate using just a light bulb? There are 100 prisoners about to serve solitary confinement. While imprisoned, no prisoner will have contact with any other prisoner – in fact, they will usually never leave their cells. However, each day the warden will pick a prisoner (either at random or arbitrarily)…

  • 2358 puzzle

    Using 4 math operationsObtain 16 using 2,3,5,8.All numbers must be used.Each number must be used once.You can put parentheses anywhere.Those are numbers, not digits, for example you cannot combine 2 with 3 to make 23.