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25 votes
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Psychology Today Culture Fair IQ test question

Here is a diagram to show what I am on about:
PDT's user avatar
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22 votes
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Leaders and Rulers

Consider the group consisting of everyone who is a ruler of at least one group. Like all groups, someone is in charge of it. If that someone is not in that group, they're its ruler, but that ...
xnor's user avatar
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17 votes

Psychology Today Culture Fair IQ test question

I have the same answer as PDT, but reached it by entirely different reasoning. Diagram:
Hunter of Wisdom's user avatar
16 votes
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What's the one digit you can fill in this partially hidden Sudoku?

I think the answer is Indeed
Jujustum's user avatar
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13 votes
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Torus Flow Free

Below is the final answer: Explanation: I think the main question is, which color will go through the center column? Note that both B and C are adjacent to the cells connecting the center column ...
Lezzup's user avatar
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12 votes
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Bare Bones – a semi-DIY crossword

Gladys is visiting: Completed grid: Across: Down Filling the grid: Finding the answer:
fljx's user avatar
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11 votes
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New record for minimally clued 7x7 Hidato (now with 6 clues!)

Is this a race to the bottom? I solved the 8- and 7-clue puzzles before you edited to make the 6-clue one. (Edit: I also added a solve path for the 6-clue) 8-clue solution 7-clue solution 6-clue ...
Benjamin Wang's user avatar
11 votes
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3-clue 5x5 Hidato

This one was tough! I managed to solve it mostly through trial and error. The vertical section between 16 and 22 is very constrained, because it needs quite a few sequences to pass through it, and ...
GentlePurpleRain's user avatar
10 votes
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66: Luftballons

Clue explanations: Dosun-Fuwari solve: And in the finished grids,
Deusovi's user avatar
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8 votes

Torus Flow Free

As in Lezzup's answer (but more formally),
AxiomaticSystem's user avatar
8 votes

Solve the Alphametic: SOUNDS / WOW = ELK

Let's start with the obvious. Next, However, All that's left now is Here's the final division problem: Putting it all together, we get our final solution:
juicifer's user avatar
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6 votes

The Room Of Tiles

I'll say that tile A "beeps" tile B if stepping on A first and then B produces a beep. If we need to be perfectly confident that our choice is safe: If we need a strategy to escape with ...
kagami's user avatar
  • 216
5 votes
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Current record for minimally clued 7x7 Hidato (16 clues)

Solution: Step by step: 1: 2: 3: 4: 5: 6:
Beastly Gerbil's user avatar
5 votes
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Reconstruct a long division given less than a quarter of the digits, and all of those are wrong

The Answer Solve Path Consider the last digit of the quotient. Since it cannot be 1, it must be at least 2; and the last multiple of the divisor is 2-digit, which implies that the divisor is less ...
ACB's user avatar
  • 7,281
4 votes
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Communicate square on a 3-by-3 grid by flipping precisely one of 13 coins

We have 13 coin positions, which I'm going to give the following names (it doesn't matter which position is given which name, it can be selected arbitrarily as long as I and my ally agree on the ...
ais523's user avatar
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3 votes
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Off-duty guards on liar island

Here's what I've got assuming the guards know each other's rules: Art: Welcome! I'm Art, this is Tony, and this is Xavier. (I could tell from their name badges that this was true) TRUE -- as given. ...
Bob Bixler's user avatar
2 votes

Solve the Alphametic: SOUNDS / WOW = ELK

Slightly different solve path:
AxiomaticSystem's user avatar
2 votes

New record for minimally clued 7x7 Hidato (now with 6 clues!)

Here is an image with the solution to the 6 clue puzzle:
mathlander's user avatar
  • 1,261
2 votes

The prisoners and the switch

You could refine the probability of success using the Coupon-Collector's distribution and one bit of info to improve on that, While not part of the question:
kagami's user avatar
  • 216
2 votes

The prisoners and the switch

Obvious 1: Obvious 2: Strategy A:
Angel Sachse's user avatar
2 votes

Leaders and Rulers

(finite case; not sure if this extends to infinite case) Suppose not; then every person in the population has to be either a leader or a ruler (or neither). In particular, a leader cannot rule another ...
azi's user avatar
  • 543
2 votes
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A Framework puzzle

Of course, we start with the 8-digit entry... Now, one slightly more advanced deduction than 'only one number fits here' is necessary. The solved grid is:
Deusovi's user avatar
  • 147k
1 vote
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Culture Fair IQ Test

Number 1 is Number 2 is Number 3 is Number 4 is
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1 vote
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Long Division when it is almost, but not entirely, wrong

Answer Solve Path It's easy to see that the last digit of the quotient is 0. The key point is the last digit of the remainder. Note that for a unique solution, the tens digits of the divisor and the ...
ACB's user avatar
  • 7,281
1 vote

Logical Reasoning - Seating Arrangement problem

Fluorine has a good point about this being poorly phrased. The question as written means "absolute left and right, the one of an outside observer" (Fluorine). Note that the originator of ...
Bob Bixler's user avatar

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