New Puzzles For Your Mind

Looks May Be Decieving:

Isaac, Galileo, and Archimedes are heading to the House of Blues to see the Joy Formidable perform. Their cab driver is taking a serpentine path, as usual, and making the trip longer than normal. When they arrive the fare is $30 and the 3 friends pay $10 each. Isaac stays behind to haggle with the gypsy cab driver and convinces him to only charge $25. Realizing the $5 change cannot be split evenly amongst the 3, Archimedes makes Isaac give the cabbie $2. Now, the 3 friends have paid $9 each ($27 total) and the cabbie has $2 tip giving a grand total of $29! Where’d the last dollar go?!

Different situation same problem:

3 guys pay $10 each for beer. The manager realizes he overcharged them and tells the store clerk to bring them $5 change. Knowing $5 can't be split 3 ways he keeps $2 for himself. When the 3 guys get their change it appears that they have all paid $9 and the store clerk kept $2 giving $29. How do you account for the missing $1?


A Favorite of Ricky Gervais:

After a brush with a 24 ft. great white shark tragically resulted in your death, you must answer the following riddle to determine your place in the afterlife:  There are two identical, but separate doors; one leads to hell and the other leads to heaven. They are guarded by 2 identical Anubis-like figures. One of the guards always tells a lie (he guards the door to hell) and the other always tells the truth (he guards the door to heaven), but you don’t know which is which. What question can you ask that will tell you which door leads to heaven (or hell if that’s what you prefer)?


Email Questions/ Answers to Naughtje@gmail.com , whoever answers the most riddles by the end of the year will win a prize.



Solutions to last week:

Jenga puzzle- the distance can theoretically be infinite, assuming you have an infinite supply of blocks. In order for the blocks to not fall over, the center of mass of the structure cannot be located beyond the table edge. The center of mass of each block is obviously at its center and the center of mass of 2 jenga blocks on top of one another is the distance halfway between their center of masses or 1/4 a jenga block to the right of the top block’s center of mass. Therefore the largest offset of 2 blocks on top of one another is 1/2 a jenga block + 1/4 a jenga block like so:


Conor Naughton | The Rock at Boston College
Now if we have 3 blocks, the center of mass of the entire structure is 1/6 of a jenga block from the edge of the bottom block. The total offset with then be 1/2 + 1/4 + 1/6 of the length of a jenga block:


Conor Naughton | The Rock at Boston College

You can see where this is going: another block adds 1/8 to the offset, another adds 1/10 to the offset… this process can go on to infinity. This is known as a harmonic series and it diverges, meaning it goes to infinity. Thus we can have an infinite offset!


Bartender Puzzle- Neither of those answers are correct because there is an equal amount in both. The total amount of liquid is the same in each glass after performing the 2 operations. Therefore, the amount of whiskey missing from the Jameson glass is replaced by the amount of ginger ale missing from the ginger ale glass, which has been replaced by the aforementioned missing whiskey.


Golden Life- Your friend threw the gold blocks into the water, causing the water level to decrease. To explain this we use Archimedes law: any floating object displaces a volume of water equal to its weight. Since gold is much heavier than water, the amount of water which it displaces when afloat is much larger than the volume of the gold block. When the block is at the bottom of the container, it only displaces an amount equal to its volume. Therefore, the water level will drop low enough for you to breathe.

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