• # Brain Teasers & Puzzles

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• There is a polynomial and you have access to a function that evaluates that polynomial at a given number.  You don’t know the degree of the polynomial, nor do you know any of the coefficients of its terms.  However, you are told that all coefficients are non-negative integers.  How many times do you need to call the evaluation function in order to identify the polynomial (that is, to figure out the values of its coefficients)?

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• There is a table with a row of 2014 cards.  Each card has a red side and a blue side.  We’ll say that a card is red if the color on its visible face is red, and analogously for blue.  Two players take turns to do the following move:  select any 50 consecutive cards where the left-most card is red, then flip each of those 50 cards (thus, for those 50 cards, turning red cards into blue cards and blue cards into red cards).  Both players look at the cards from the same side of the table, so “left-most” means the same to both of the players (that is, you can think of one of the ends of the table as being designated as the left end).  When it is a player’s turn, if that player cannot make a move (that is, if there is no way to select 50 consecutive cards the left-most one of which is red), then that player loses and the other player wins.  If you are one of the players and all cards are initially red, can you be sure to win, and if so, do you want to be the player who goes first or second?

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• Two arbitrary rectangles are placed to form an “L”.  That is, the lower left-hand corner of the two rectangles share the same point. (What I’m trying to say is that there’s an “L” whose “I” and “_” parts have arbitrary widths and heights.) Using only a (pen and a) straightedge (that is, no measuring device and no compass), figure out a way to, with a single straight cut, divide the “L” into two pieces of equal area.

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• A homicide team enters a crime scene where a dead body of a fat old man lies there on the floor with blood oozing out of his head. The victim is holding a gun and a tape recorder lies there by his side. One of the detective picks up the recorder and plays it “I am tired of this life and hence I have decided to relieve myself from the worldly pains”. A gunshot follows the message.

The teams starts investigating a murder investigation.

Why?

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• You had an infinite supply of water and a 5 ml and 3 ml gallons.

How would you measure exactly 4 ml in least number of steps ?

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• A guy claims to do the following thing. He puts a coin in a glass bottle. Then, he shuts the mouth of the bottle with the help of a cork. Now he manages to remove the coin out from the bottle without taking out the cork or breaking the glass bottle.

Do you know how he can do it?

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John123 Expert
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• Complete the pyramid my replacing ? with the correct number.
1
1 1
2 1
1 2 1 1
1 1 1 2 2 1
? ? ? ? ? ?
? ? ? ? ? ? ? ?

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John123 Expert
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• A conference room contains three separate wall-mounted spotlights – right, left and front of stage. Each is controlled by its own on-off switch. These three switches are numbered 1, 2 and 3, but they are in a back-room which has no sight of the the spotlights or the conference room (and there are no reflections or shadows or mirrors, and you are alone). How do you identify each switch correctly – right, left, front – if you can only enter the back-room once?

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John123 Expert
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• ## More puzzles to try-

• ### Fair soccer championship

The games played in the soccer world championship form a binary tree, where only the winner of each game moves ...Read More »
• ### Ratio of boys to girl riddle

The overly feminist rulers of a country decide that there are too many baby boys being born. The rulers decide ...Read More »
• ### Can you see both the duck and the bunny in this ambiguous drawing?

Can you see both the duck and the bunny in this ambiguous drawing? The duck’s bill is the bunny’s ears. ...Read More »
• ### How many ducks are there?

Two ducks in front of a duck, two ducks behind a duck, one duck in the middle How many ducks ...Read More »
• ### Find the next number in the sequence

What is the next number in this series? 1, 2, 6, 42, 1806?Read More »
• ### 4 Weight bars to weigh given wieght puzzle

You  have to take 4 weight bars (all of integer values). Using only those 4 bars  you can weight all ...Read More »
• ### River and Boat riddle

John and Jacob are on the two opposite banks of a river. They both have a rowing boat. They both ...Read More »
• ### Penguins and their money riddle

Where do penguins keep their money?Read More »
• ### Bus moving left or right – Easiest but the toughtest puzzle to fry

In karol Bagh,Delhi,India from puzzleFry’s office window  i saw this bus and confused Which direction is the bus going, Can ...Read More »
• ### Baby child name Puzzle

Lady Gaga is pregnant and currently has 6 daughters 1. Dorry 2. Rebeka 3. Michael 4. Faniya 5. Sophia 6. ...Read More »
• ### Handshakes riddle

In a get-together i counted the number of handshakes that were exchanged. There were 28 altogether. Can you tell me ...Read More »
• ### You are glad to find me riddle

You are glad to find me when you need me, or you always ignore me. When you call me, I ...Read More »
• ### Do you know what that integer is

A special integer exists in mathematics that shows a special property. If you subtract any number from that integer, the ...Read More »
• ### BOXES WITH MARBLES

You have three boxes full of marbles. There are stickers saying “white” “red” “red and white” on them indicating what ...Read More »
• ### All have me

When you have me not, you want me. But when you have me, you do not know. What am I?Read More »
• ### Maximum distance travelled by scooter puzzle

There is one scooter which has 2 tyres and one stepney/spare (i.e. total 3 tyres). Each Tyre can run up ...Read More »
• ### 100 meters race riddle

Akash, Andrew, and Allen race each other in a 100 meters race. All of them run at a constant speed ...Read More »
• ### Swimming competition final seconds riddle

You are participating in the swimming finals at the Olympics. In the final few seconds of the race, you narrowly ...Read More »
• ### Can you find out the result of the individual games?

Aaron, Brad, Christopher, Danny and Elvis decided to play a game of tiddly winks. In this game they decided that ...Read More »
• ### Why johnny is not wrong?

Little Johnny’s teacher asks him, “If I gave you two cats, then two more, and two more cats; how many ...Read More »