Riddles to Tease Your Mind


Lockers

You are standing in front of a row of one hundred lockers in a school each is numbered one, two, three, and so on to one hundred.  There are one hundred students each assigned a single number one through one hundred.  They go in turn starting with student number one and change (open a closed  or close an open locker) every "xth" locker associated with their number. i.e. to begin with all are closed.  the first student "changes" every 1 lockers so he opens them all... the second student will change" every second locker (since # 1 has opened them all #2 will close every 2nd locker)... the third student will change (if a locker is open he closes it if closed he opens it) every third locker... this goes on through all one hundred students.  At the end of the ordeal which of the lockers will be open? 

Solution


Chess

Consider a chessboard with a single Rook. A Rook can move any number of square sideways/forward, but not diagonally.
What is the minimum number of moves the Rook needs to make, in order to pass over all the squares on the chessboard and return to the original position?
Note: Take any square as a starting position for the Rook.

Solution


Scandal

Assume that you have just heard of a scandal and you are the first one to know. You pass it on to four person in a matter of 30 minutes. Each of these four in turn passes it to four other persons in the next 30 minutes and so on.
How long it will take for everybody in the World to get to know the scandal?
Assume that nobody hears it more than once and the population of the World is approximately 5.6 billions.

Solution


Name

When you say my name I don't exist anymore
who am I?

Solution


House

If you built a house, with all four sides facing a southern exposure, and a bear walked past, what color  would it be?

Solution


What is it?

1.The person who buys it doesn't need it
2.The person who makes it doesn't want it
3.The person who uses it doesn't know it
What is it?

Solution


Leaving Home

A man leaves home takes three left turns and arrives back home only to find to me awaiting him with masks on.  What happened?

Solution


Light Bulbs

A man is given the following test to solve.  He is placed before a completely enclosed room.  He is standing outside the only door to this room.  Next to the door are three light switches.  The door is closed.   Inside the room are three light bulbs corresponding to the three light switches on the outside.  The objective is to match each switch to its corresponding lightbulb. He is told that he can fiddle with the switches any way he would like, but that he may open the door and enter the room only once and than when he exits he must immediately tell which switch matches which light.  The door is positioned so that he cannot open it and see or touch the switches while it is open.  What should he do? 

Solution


Hats

An executioner is holding four men. He instructs them that he will kill them all if they cannot pass the following test.  He will place all four of them in a single file line facing the same direction one behind the other.  He places a brick wall behind the first man so that none of the three behind him can see him.  He tells the men that he has 4 hats, 2 black, 2 white. He places a single hat on each man's head in such a manner that the man can only see the color of the hat of the person(s) in front of them (other than the first man who is in front of the brick wall and no one can see him-and he can't see anyone).  The executioner instructs the men that one person can save all 4  of them if he can tell the executioner what color hat he has on.  Assume you are a bystander and can see that the executioner has placed the hats in the following order starting from the back person "white,black,black, white"?  What if you saw that the executioner had put their hats on in this order starting from the backmost person- "white,black,white,black" In each of these cases, who should speak up and be correct 100% of the time?  (there are no tricks... no one can see the color of his own hat in any way).

Solution


Quarters

Imagine filling Brian's office space at work (a room about 9.5' by 12') entirely full with quarters.  You then take this amount of quarter and stack them into one tall pile... Will this pile be taller than the empire state building?

Solution


Number Sequence

Continue the following sequence of numbers

0    10    1110    3110    132110     _____________

Solution


Connecting the Dots

Connect all the dots in the diagram below with 4 straight lines without lifting your pen from the page (you can recreate the image on paper and try this)

 

0        0        0

0        0        0

0        0        0

Solution


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