Captain Brownbeard’s hourglasses

Captain Brownbeard of the pirateship “The northern star” told his first officer: “Tonight I want to sleep for 7 hours. Wake me exactly 7 hours after I leave the bridge.”

The unfortunate first officer knew that captain Brownbeard had only 1 punishment: eat so many chocolates that you never can stand the sight of chocolate again. He didnt want to suffer such a dreadful fate. To make things worse, he had only two hourglasses, one of 5 hours and one of 3 hours. How can he measure exactly 7 hours? Does he need to make any preparations in advance, and if so, which?

This puzzle is based on a puzzle with hourglasses of 4 and 7 hours which I found in both “More games for the superintelligent,” by James F. Fix and in “Denkspielereien” by Tom Werneck. The same problem can be found on numerous places on the web, with hourglasses of 7 and 11 minutes. This raises of course the question who invented this puzzle, and when?
Oh, by the way, the times used in this puzzle introduce a slight variation.

You can check your solution

Pattern code snakes

1) Snakes
What is the code that goes into the question mark?

You can check your solution

A lightbulb and three switches

1) Three switches^*
In a room, there is a light-bulb hanging down from the ceiling. Its door is closed, and from the corridor outside you can not tell if the light-bulb is burning or not.

In another room there are three switches, one of which controls the light-bulb – but you don’t know which one. The three switches are all in their ‘off’ position.The two rooms are several corridors apart. Assuming you don’t want to walk more then necessary, how often do you have to check the room with the light bulb in order to find out which of the three switches controls the light bulb?

Kees Krol recently reminded me of this problem, though he or someone else showed me the problem some time ago.

If you think you solved this puzzle, you can check your solution here

Pattern codes – signalling people

1) Signalling people^**
Have you ever seen the people on an aircraft carrier, or in the mountains, signalling an helicopter to get down at a specific point?

This puzzle is inspired by those people and signals.

solution

Did you know….
Body language provides a much better cue than facial expressions when judging if a person has just gone through severe emotions?
See here for more details.

Pattern code lines

1) Pattern code lines^*

As in previous puzzles of this type, every letter corresponds with a property of the figure.

solution

Medals

For the Puzzle-Olympics, the International Brain Olympics Committee is purchasing gold, silver and bronze medals. In the medal shop, the bronze, silver and gold medals each have their own prize. Unfortunately for the procurement officer, only sets have price labels.

What is the prize of the fourth set?

If you are puzzled, we have a hint for you.

Cubes

Cubes are wonderful things. With six side surfaces, eight vertices and 12 edges, they are highly symmetrical. There are 11 ways to flatten a cube into a plane by cutting the edges. Here are 6 of the 11 ways:

Can you tell which cube is different? You can ignore the orientation of the letters – they are merely for identification. The symbols have been added for those readers who are colourblind.

If you are puzzled, we have a solution for you.

Did you know?
The subiculum plays a role in spatial navigation, mnemonic (symbol) processing. You probably already understood that this puzzle challenges the 3D representation facilities of your brain.

Books

1) books^*
The professors assistant entered the office room of the professor and noticed that the professor had not only labeled the plants as shown in a previous post, but also his books. Only a new book on his desk was not yet labeled. Can you help him out?

You can look up hint here.

As you may have noticed I like this type of puzzle. Though I am no brain expert, i think you need to active different parts of your brain, and though I’m no expert in the field here’s a list of those parts of the brain which i think will be utilized while solving these puzzles:

• According to research by J. R. Binder and others, the Angular gyrus was used heavily when processing abstract keywords. Finding the correct abstract concepts play an important role in these puzzles.
• Prefrontal Cortex: used for: planning, reasoning, and judgment. Once you have an idea which properties of the objects play a role in the codes, you will need deductive reasoning to check that. Deductive reasoning activates the left frontal lobes, as researched in a meta study in 2011 by Jérôme Prado, Angad Chadha, and James R. Booth.
• The Occipital Lobes are used by visual activities, and as these puzzles are highly visual the solver needs to use this part of his/her brains.
• The inferior frontal gyrus and middle temporal gyrus are utilized according to research by Jing Wang, Julie A. Conder, David N. Blitzer, Svetlana V. Shinkareva.
• Corpus Callosum: This allows information to move between the left and right hemispheres of the brain and is thus a very important integrative structure.

Next weekend we hope to be away a few days, so the puzzle may be later than usual.

Pattern – flowers

When the new assistant of Professor F. Lower walked into the lab, he noticed that the professor had labeled 5 of the plants. The professor seemed to have walked out of the lab without labeling the sixth plant. Can you help out the assistant?

You can look up a Hint