About this blog

Among the moments of my childhood, I keep with special affection the memory of playing puzzles with my brothers. Some of these puzzles struck me and made me understand that to solve a problem (either real or fictitious) must cover all its facets and edges, and it is necessary to rethink the same problem from different points of view. 

When I was a teenager and I was sharing experiences with my friends, I was surprised to note that some of them knew many of the conundrums that fascinated me, we could even exchange a few others. Today I love puzzles raise my daughter and my nephews, and comfort me much satisfaction watching their faces reflected the same feelings and emotions that seized me and my brothers several tears ago.

The desire puzzles, riddles and questions is certainly inherent in human nature, reflections of this desire we find in literary works of all times and places ( " Oedipus"  and " The Hobitt"  are some of my favorite examples) also in film (eg the great " into the labyrinth" ).

It is my desire to share in this blog the mind games that I like and that struck me most as a child, with the motivation to stimulate thinking and imagination of new minds.  

I hope that you enjoy it.

Riddle 1: Two Doors

The two doors

The following is an adaptation of one of the most famous riddles, the riddle inspired by " knights and squires , " which was popular in the mid-twentieth century. Can be found in many forums, books of riddles and in the film  Labyrinth ( "Labyrinth", 1986) , where  the great  David Bowie  played  the role of  Jareth, the king of the goblins , who from here manuf you tribute.

" You are a prisoner in a cell where there are  two doors guarded by  two guards  in front of each of them. One door leads you into a  labyrinth  from which you can never leave, while the other leads you to  freedom . You know one of the guards always tells  the truth  and the other always  lies , but you do not know who is who. Your  captor  Jareth, the king of the goblins, gives you the opportunity to cross one of the doors after making  one question  to one of the guards. What question would you do to find out  what is the door  that will lead you to  freedom ?.

Solution Riddle 1

SOLUTION RIDDLE 1:

If we asked one of the guards "What answer me the other guard if I ask what is the door that leads me to freedom", we will know which is the door that we want to cross, which is the opposite of that tells us, since:

• If we were asking the guard who always tells the truth, it would indicate a door that would actually be the door that leads to the maze with no exit, which is the door to tell his companion that always lies.
• If we were asking the guard who always lies, also you tell us a door that would be the door that leads to the labyrinth without exit, since we say the opposite of what he would say his partner, who would tell us what is the door It leads to freedom.

Riddle 2: Cheryl´s Birthday

Cheryl's Birthday

This time I present the famous problem recently raised at the Olympics in math Asia and Singapore from 2015 to kids in high school, which has already converted in viral on social networks, which is a sign of the interest that may raise a good conundrum in the general public. In the illustrations of this riddle I pay tribute to the great actors of an excellent movie that I recommend: "Philadelphia Story (Philadelphia Story, 1940)".

" Albert and Bernard have recently met Cheryl, and both want to find out when it's your birthday. Cheryl gives them a list of 10 possible dates:

-        May 15

-        May 16

-        May 19

-        June 17

-        June 18

       

-        July 14

-        July 16

-        August 14

-        August 15

-        August 17

Cheryl tells Albert and Bernard separate the month and day of your birthday respectively.

Albert:           I do not know when Cheryl's birthday, but I know Bernard does not know.

Bernard:       At first I knew when it was Cheryl's birthday,  but now I know.

Albert:          Then I also know when is the birthday

Cheryl.

So when is the birthday of Cheryl ?.

Solution Riddle 2

SOLUTION RIDDLE 2:

When reading the problem statement , one can stay stunned and go blank. However, anyone who has a little experience in addressing problems of logic and learn how to use the basic logic, perhaps for being a faithful follower of this blog; ),  can reach the solution, since no it is an extremely difficult problem; however you have to combine various mental processes, so it is an excellent exercise for the brain.

Let the matter:

We have 10 dates, with 6 numbers we see that some numbers are repeated except 18 and 19. Albert knows only the month of the birthday of Cheryl, and Bernard only knows the number.

In the first comment of Albert, who remember who knows the birthday month Cheryl tells us that you do not know your birthday but know that Bernard (who knows the number but not the month) does not know either. Bernard could only know the birthday if he knew the number was 18 or 19, which are the numbers that are not repeated in the list given by Cheryl. For Albert knew that Bernard does not know the birthday, it should fall into a different month to appear with the numbers 18 or 19. We are then 5 dates, July and August:

-        14 and 16 July

-        14, 15 and 17 August

With commentary by Bernard indicating that after the comment of Albert already know the date of the birthday, we infer that the number of the date that he knows should not be repeated in the list above, then, of those five dates must discard dates there are any number to repeat, staying only 3 dates:

-        July 16

-        15 August 17

Now in the second comment of Albert (who knows Cheryl's birthday month) it says that from the comment of Bernard and also knows that date is the birthday of Cheryl. As he knows the month, the birthday should be the July 16 , as if it were the birthday in August would have no way of knowing if the birthday is on 15 or 17 August.

Riddle 3: The Explorer and the Cannibals

The Explorer and the Cannibals 

"A reckless explorer was captured by cannibals who wanted to eat him, and said, "If you say a lie we kill slowly , and if you tell a truth we will kill you quickly". The explorer told them something and cannibals chose not to kill him. What could have told them not to kill him for? ".  

Solution Riddle 3

SOLUTION RIDDLE 3:

He could have said:   "I am going to kill you slowly."  That way, if they consider truth, in his words should kill quickly, which would make the browser statement was a lie. Should they lie they should kill him slowly, which would make the statement browser was true.