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Logic and Lateral Thinking

Picture of mouse in a cardboard maze. It has eaten its way through the walls directly to the cheese.Picture of a Maze with a line drawn directly from one side to the other with the word Parkour written underneathSometimes we assume too much when we think.  We place restrictions on our thinking that the ‘rules’ never made explicit.

The mouse in the illustration was under no obligation to follow the maze.  I also have a T-Shirt with the picture at right.  I guess free runners have the skills to leap over tall buildings and …


This page will be used for serious logic questions as well as the more light-hearted and lateral question as well.


Transferring Liquid Between Beakers

Two beakers with different coloured liquids in themYou have a beaker containing exactly 200 mL of pure water.  You have a second beaker containing exactly 200 mL of pure alcohol.

They can mix, but they are chemically different.

You take one teaspoonful of water and drop it in the beaker containing alcohol.  You now take one teaspoonful of the mixture and return it to the beaker of water.

Now, is there more alcohol in the water, or more water in the alcohol?

Answer: Answer to the liquid transfer puzzle.

The Local Barber

Young adult male getting hair cutIn a small country town everyone has regular haircuts.

All haircuts are carried out within the township.  Some people prefer always to cut their own hair.  The others always get the village barber to cut their hair.  The village barber also lives in the town.

Now, just to make the conditions perfectly clear ... no one, except the barber, ever cuts anyone else's hair. And none of the men who cut their own hair ever let the barber touch it.

Question: Who cuts the barber's hair?

Answer: Answer to the village barber question

Brilliant!!! This helps so much!!! So much easier than anything else I have found. This is now simple.
Thanks again for showing the simple way of doing this. I look forward to the next video!! Absolutely brilliant.
Once again, excellent! I’ve watched many others, that have not helped nearly as much as these. Thanks for making it so easy to understand. When things get complicated, it is easy to make a mistake, but your method of writing down the structure helps to prevent mistakes.
Thanks a million!!! I’ve watched many videos and read tutorials, but still could not get two in a row correct on Khan Academy. Your explanation was so clear and simple that it finally made sense to me and now I can get all of the problems correct!!! Thank you very much.
It all makes total sense now! Thanks very much for all the derivative videos!!! Very helpful.
MemorizeAndLearn (on four different CCM YouTube videos about Differentiation)

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