**Twenty Questions** is a popular game which encourages deductive reasoning. Usually, one person is chosen to be the answerer. That person chooses a subject but does not reveal this to the others. All other players are questioners. They each take turns asking a question which can be answered with a simple “Yes” or “No”. Lying is not allowed, as it would ruin the game. If a questioner guesses the correct answer, that questioner wins and becomes the answerer for the next round. If **20 questions** are asked without a correct guess, then the answerer has stumped the questioners and gets to be the answerer for another round.

The above game is called 20Q and you can play it online at 20Q.net.

Now for some math:

The

game is often used as an example when teaching students about

information theory. Mathematically, if each question is structured to

eliminate half the objects, 20 questions will allow the questioner to

distinguish between 2^20 or 1,048,576 objects. Thus, the best strategy

for 20 Questions is to ask questions that will split the field of

remaining possibilities roughly in half each time. This process is

analogous to a binary search algorithm in computer science.

cool!!! ðŸ˜›

0 0