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1500 questions
40
votes
5 answers

A Suspicious Mail

It's an average normal everyday day. You find a piece of mail in your mail box. It doesn't look like the rest of them: The text reads VVJHRU5UISBQbGVhc2U gYXR0YXRjaCBvdXIgbmV4dCBsaW ZlIGFuZCB5b3VyIHB1YmxpYyBrZXk gYW5kIHJldHVybiB0byB1cyB3aXR …
pfg
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Break the subsitution cipher with a twist

Breaking news: the NSA can break letter substitution ciphers. (Letter frequency, guessing the word "the", et cetera...) So, let's make our secret code more secure. Let's apply the secret substitution n times to the nth letter of the message. Here's…
Lopsy
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40
votes
3 answers

Twisted TV Titles

This is a puzzle I created for a road rally / puzzle hunt a few years ago. It shouldn't be very difficult but hopefully will be a bit of fun. This is my first puzzle, so I welcome any feedback in the comments. TWISTED TV The creators of this…
Pugmonkey
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votes
6 answers

Changing baby's shirt

Baby needs a change of shirt, but baby is also sucking on a bottle (see this stock photo for a visual). If the bottle leaves baby's mouth, baby will start crying. Also, baby loves holding the bottle himself, so he needs to be holding the bottle…
Tyler Seacrest
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40
votes
5 answers

Duel between the knight and the dragon

A dragon and a knight live on an island where the only sources of fresh water are a pond (containing ordinary water) and six wells, numbered 1 to 6. Each well's water is completely indistinguishable from the pond water, but contains a magical poison…
Neil
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votes
3 answers

How many liars are in the room?

There are five people in a room. Each person is either a knight, who always tells the truth, or a liar, who always lies. Each person is asked the following question: How many liars are among you? The answers are: "one", "two", "three", "four",…
Smart
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votes
6 answers

Sudoku embedded in a Kakuro

In addition to standard Kakuro rules, the grey shaded cells must form a valid Sudoku solution. One sum in this puzzle has been corrected from 28 to 23. Fortunately, it was in a location that nobody has resolved yet, so everybody's progress up to…
paramesis
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votes
5 answers

Making 103 from 4 zeroes

As the title suggests, the puzzle here is making the number 103 by using exactly four 0s and the following operations: $+$ Addition $-$ Subtraction $\times$ Multiplication $\div$ Division $\sqrt{a}$ Square Root $\sqrt[b]{a}$ Arbitrary Roots $!$…
noneuclideanisms
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votes
1 answer

Yes, your fat ma is hers

Inspired by Elephants always get four mice. Start with the phrase Yes, your fat ma is hers and perform the following steps, in some order, to find a famous quote: Rearrange the words. Remove a single letter from one word. Reverse one word. Remove…
Rand al'Thor
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votes
1 answer

What number should be the answer to this question?

Now that my first puzzle's done and gone it wont be so easy to solve the rest. I've begun to write with reestablished rules. If I've not got your attention I'll start trying harder. So weigh the options and look closely, It shouldn't be hard for you…
mkinson
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40
votes
1 answer

Introducing: Number Slope™

Number Slope™1 is an original2 grid deduction puzzle similar to Sudoku. It is solved on an n-by-n grid, tiled with n n-ominoes. The rules are: Each number from 1 to n must occur once and only once in each row, column, and n-omino. Any row or column…
Volatility
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40
votes
6 answers

One rectangle, indivisible

Here is a rectangle made out of 2x1 dominoes: It can be divided along a line into two smaller rectangles: What is the smallest (in area) rectangle of (edit) multiple 2x1 dominoes that cannot be split along a line into two smaller rectangles?
Owen
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votes
3 answers

Here's what I do, tell me what I am

As a whole, I can Decide how serious or down-to-earth you are, Arrange a trip for you, or even Pull your leg! Remove the first three vital letters of me, and I am Dying of gloom and dullness, Solving puzzles in a shrine, Not the one making your…
Ankoganit
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40
votes
4 answers

Turn 4x4x4 Rubik's Cube into 3x3x3 Rubik's Cube

I have a 4x4x4 Rubik's Cube, but all I want is a normal 3x3x3 Rubik's Cube. Luckily, I also have an unlimited supply of small pieces of tape. Each piece of tape can cover the face of two neighbouring squares on my Rubik's Cube. When two pieces are…
JenserCube
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40
votes
3 answers

No, It's Not A Polynomial

There is a simple way to generate every one of the thirty-seven numbers below. They form a closed set; that is, there are no more numbers with this property. My apologies in advance if this doesn't go as planned. This is my first number pattern and…
Hugh Meyers
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