Famous Riddles

Some of the most famous riddles in the world. They’ve been passed down for generations, and are renowned for their ingenuity and universal appeal.

12th Floor Elevator

A man lives on the twelfth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator or if it was raining that day, he goes back to his floor directly. Otherwise, he goes to the tenth floor and walks up two flights of stairs to his apartment that is on the twelfth floor. Why?

Riddle Answer

The Missing Dollar

Three men go to stay at a hotel and they are charged $30 for the room.

They split the cost with ten dollars each.

Later the manager finds out that the rate is $25 and gives the bellboy $5 to return to the guests. On the way to the room the bellboy reasons that $5 would be difficult to split among three people so he pockets $2 and gives $1 to each person.

Now each person paid $10 and got back $1. So they paid $9 each, totalling $27. The bellboy has another $2, adding up to $29. Where is the missing dollar?

Riddle Answer

The Three Gods

Three Gods A, B, and C are called, in no particular order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter.

Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one God. The Gods understand English, but will answer all questions in their own language, in which the words for yes and no are “da” and “ja”, in some order. You do not know which word means which.

  1. It could be that some God gets asked more than one question (and hence that some God is not asked any question at all).
  2. What the second question is, and to which God it is put, may depend on the answer to the first question. (And of course similarly for the third question.)
  3. Whether Random speaks truly or not should be thought of as depending on the flip of a coin hidden in his brain: if the coin comes down heads, he speaks truly; if tails, falsely.
  4. Random will answer “da” or “ja” when asked any yes-no question.

What would your three questions be?

Riddle Answer

King Octopus and Servants

King Octopus has servants with six, seven, or eight legs. The servants with seven legs always lie, but the servants with either six or eight legs always say the truth.

One day, 4 servants met:
The blue one says: “Altogether we have 28 legs”;
The green one says: “Altogether we have 27 legs”;
The yellow one says: “Altogether we have 26 legs”;
The red one says: “Altogether we have 25 legs”.

What is the colour of the servant that is speaking the truth?

Riddle Answer