Brain Teasers

How Many Knights?

In chess, a knight moves two squares in one direction and one square in another direction, ending up on the diagonally opposite corner of a 2 x 3 grid. Intervening squared can be occupied.

Find the maximum number of knights which can be placed on an 8 x 8 chess board so that so that no knight threatens another knight (can move into a square occupied by one of the other knights).

What is the placement of the knights on the board?

Get the answer to How Many Knights?

Thank you Daryl Cooper

Mapping Puzzle

Take a map and connect each town shown on it to its nearest (as the crow flies) neighboring town using a straight line segment. Assume that each different pair of towns is a different distance apart. What is the maximum number of towns that any one town can be connected to?

Get the answer to Mapping Puzzle.

Thanks to Technology Review.

Five Cube Calendar

There are five cubes which together can be used to display any day of the year in the form 21MAY.

The first two cubes contain the dates. Each face has a digit. The 6 also fills in for the 9. Arrange these two cubes can make any date from 01 to 31. Also, for one cube, the sum of the digits is a perfect square.

The remaining three cubes have a letter on each face. There are no repeats. They can be arranged so that the front faces display the first three letters of each month, except August which is displayed as VAC since so many people are on vacation during that month.

What other digits are on the same cube as the 6? What other letters are on the same cube as the E?

Get the answer to Five Cube Calendar.

New Scientist

Try our other brain teaser puzzles and find out how smart you are. Have some brain game fun!

Einstein's Logic Puzzle Albert Einstein is reported to have said that 98% of the world's population could not solve this hard brain teaser puzzle.	Emergency Flight Brain Teaser A sick sailor needs medicine. None of the available planes can carry enough fuel to make the trip and also return. How can they save the sailor?	Fix the Hole Puzzle Can you figure out how to piece this carpet back together with only two cuts?
Logic Puzzle Using the clues, can you solve this logic puzzle and figure out which of the four people is Mr. Lighter?	Take a Walk Brain Teaser Can you help Mrs. Keller with this scheduling problem?	Too Many Names How can Professor Googendorf remember all the names of his students?
Tricky Triangle Puzzle Can you explain why rearranging the pieces creates an extra space?