Author: Robert

Objective / Rules– There are many Islands, each Island has a number. - This number is how many bridges leave that island. - Your must connect every island, so that all island can be reached from any other. - A maximum of two bridges can connect two islands together. - Bridges can only go horizontally or vertically and may not cross each other.

The Castle
A square medieval castle on a square island is under siege. All around the castle there is a square moat 10 meters wide. Due to a regrettable miscalculation the raiders have brought footbridges, which are only 9.5 meters long. The invaders cannot abandon their campaign and return empty-handed. How can the assailants resolve their predicament?
Virile Microbes
A Petri dish hosts a healthy colony of bacteria. Once a minute every bacterium divides into two. The colony was founded by a single cell at noon. At exactly 12:43 (43 minutes later) the Petri dish was half full. At what time will the dish be full?
Bulbs
This is one of my favorite free printable logic puzzles with a real life solution. There are three switches downstairs. Each corresponds to one of the three light bulbs in the attic. You can turn the switches on and off and leave them in any position. How would you identify which switch corresponds to which light bulb, if you are only allowed one trip upstairs?
The Ball
How can you throw a ball as hard as you can and have it come back to you, even if it doesn't bounce off anything? There is nothing attached to it, and no one else catches or throws it back to you.
Sheikh's Inheritance
An Arab sheikh tells his two sons to race their camels to a distant city to see who will inherit his fortune. The one whose camel is slower wins. After wandering aimlessly for days, the brothers ask a wise man for guidance. Upon receiving the advice, they jump on the camels and race to the city as fast as they can. What did the wise man say to them?