This puzzle is attributed to Albert Einstein. He claimed that 98% of the world could not work it out. Can you?
There are five houses in a row and in five different colors.
In each house lives a person from a different country.
Each person drinks a certain drink, plays a certain sport, and keeps a certain pet.
No two people drink the same drink, play the same sport, or keep the same pet.
- The Brit lives in a red house
- The Swede keeps dogs
- The Dane drinks tea
- The green house is on the left of the white house
- The green house owner drinks coffee
- The person who plays polo rears birds
- The owner of the yellow house plays hockey
- The man living in the house right in the center drinks milk
- The Norwegian lives in the first house
- The man who plays baseball lives next to the man who keeps cats
- The man who keeps horses lives next to the one who plays hockey
- The man who plays billiards drinks beer
- The German plays soccer
- The Norwegian lives next to the blue house
- The man who plays baseball has a neighbor who drinks water.
Use exactly four 4's to form every integer from 0 to 25, using only the operators +, -, x, /, () (brackets) x2 (square), and ! (factorial).
Example: 0 = 44-44
(Note: people have managed to do this for 1000s of numbers!)
The Monty Hall Problem gets its name from the TV game show, “Let’s Make A Deal,” hosted by Monty Hall. The scenario is such: you are given the opportunity to select one closed door of three, behind one of which there is a prize. The other two doors hide “goats” (or some other such “non–prize”). Once you have made your selection, the host will open one of the remaining doors, revealing that it does not contain the prize. He then asks you if you would like to switch your selection to the other unopened door, or stay with your original choice. Here is the problem: Does it matter if you switch?
This problem is quite interesting, because the answer is felt by most people—including mathematicians—to be counter–intuitive. For most, the “solution” is immediately obvious (they believe), and that is the end of it. But it’s not. Because most of the time, this “obvious” solution is incorrect. The correct solution is quite counter-intuitive. Furthermore, I have found that many persons have difficulty grasping the validity of the correct solution even after several explanations.
Attempt to solve this problem by yourself. You have a good chance to do so, because you now know not to trust your instincts in this and that you should consider the problem very carefully. Try it.