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Questions tagged [explanation]

The answer to a problem may be known but it is not understood. These questions explicitly request additional details on how a problem is solved or why the current solution is appropriate.

2
votes
1answer
125 views

Pattern Recognition: $7 \star 8$ =?

The following pattern was given to me by one of my friends: If $$\quad 5 \star 5 = 10$$ $$\quad 6 \star 6=18$$ $$\quad 7 \star 7=36$$ then $$\quad 7 \star 8 = ?$$ a) $54 \quad$ b) $51 \...
4
votes
2answers
221 views

What's the problem with the prisoner to be hanged logic puzzle

A criminal is imprisoned on Monday, and told "you will have been hanged by the weekend, but you won't know which day we'll hang you." If it gets to Thursday midnight and he's not been hanged yet, he ...
3
votes
12answers
2k views

English Logic Puzzle [closed]

On this site, I found this: "If some Smaugs are Thors and some Thors are Thrains, then some Smaugs are definitely Thrains." Options: TRUE, FALSE, NEITHER The answer given is FALSE. However, I ...
2
votes
2answers
93 views

Astonishing Analogies

An analogy can compare a comparison. What is the answer to the following question? Alarm is to Bread as Course is to Dot - Explain
-2
votes
1answer
451 views

What is the correct solution to 16/4(4)? [closed]

This has been circulated recently. We all know the order of the calculation: BEDMAS. B rackets and Parentheses: First Priority E xponents: Second Priority D ivision: Third Priority M ultiplication: ...
4
votes
10answers
14k views

How to prove that this man has a profit of 20 and not 10?

This is not actually a puzzle per se, but I'm asking for an explanation about the puzzle's answer. The puzzle goes like this: A man bought a goat for 60. He then sold it for 70. Later, he bought ...
6
votes
2answers
222 views

Teacup geometry

Inspired by the three utilities puzzle from prog_SAHIL I'm now posting a similar puzzle that makes use of the topology of a cup with a handle: The question is: How many distinct points can you ...
6
votes
1answer
162 views

How many dimensions?

You have $n+1$ points in $n$-dimensional Euclidean space, such that the mutual distance between each pair of points is the same. Now imagine an $n$-dimensional generalization of a sphere, such that ...
5
votes
2answers
486 views

two of A, B and C in each row column and diagonal

This puzzle comes from a book called "Braintraining Puzzles" (The one with a blue-green cover). It involves a 6x6 grid which needs to be filled with two copies of A, B and C in each row, column and ...
3
votes
1answer
1k views

Alternate answer to the 2 guard 2 door question?

I asked a friend the classic question about the two guards and two doors that goes as follows: The rules are clear: there are two doors. One leads to the castle, the other, to certain death. You may ...
10
votes
1answer
1k views

How do I solve this logic puzzle?

I am trying to improve my logical thinking and I came across this puzzle problem. I need some help solving the puzzle below. Two weeks ago, four enthusiasts made sightings of objects in the sky in ...
6
votes
5answers
27k views

Why does this answer to “two doors with two guards” work?

On this post: Two doors with two guards - one lies, one tells the truth the most common answer for this riddle is given. However, while the answer marked as correct is the most common solution I ...
7
votes
5answers
1k views

Single letter chemical elements on a 2x2 grid

In the past somebody showed me the puzzle below. I remember the answer but not the entire solution. Here it goes: On a grid of 2x2 put four single letter chemical elements. The result should have ...
14
votes
3answers
1k views

Logic behind numeric sequence

There was this sequence on a magazine and the reader has to find the next number: 10, 2, 4, 6, 2, 8 I couldn't find one, then I found the answer in the next magazine. They say the number is 5, so ...
17
votes
1answer
721 views

Salon workers, for short?

The clue is "Salon workers, for short?", and the answer is "EDS". I've spent hours trying to find an EXPLANATION for this answer. Why are there so many sites that simply GIVE you the answer without ...
1
vote
4answers
526 views

Clock time Puzzle

What will be the time when the hour, minute, and second hands will all coincide in between 6 O'Clock and 7 O'Clock? How should I approach this type of question? Can anyone explain it?
6
votes
1answer
507 views

Why are these shapes impossible to draw with the given rules?

The image above shows a group of shapes, all with lines leading to their center point. These shapes cannot be drawn with the following rules: You may not trace over over an already existing line. You ...
5
votes
0answers
2k views

Mensa IQ test question: complete the logical sequence [closed]

I tried taking the Mensa practice test. One of the question involved completing a series of figures with the most logical option. This is the base sequence: And we have to choose the additional ...
2
votes
3answers
553 views

Clarifications on the unexpected hanging paradox

I read through the wiki on the unexpected hanging paradox . A judge tells a condemned prisoner that he will be hanged at noon on one weekday in the following week but that the execution will be a ...
5
votes
1answer
403 views

Optimize cloth usage

A factory that manufactures clothing cuts multiple garments at once. Sometimes a number of markers are used for a job. Each marker may have a single size or multiple sizes depending on what is needed....
7
votes
4answers
7k views

Malcolm Gladwell's Outliers - Progressive Matrices Puzzle

In Outliers, Malcolm Gladwell presents the following puzzle: ...
7
votes
1answer
593 views

mistakes in analogous puzzles from The Tipping Point

In the book 'The Tipping Point', Malcolm Gladwell cites two puzzles and draws an analogy between them, in fact he claims the two are equivalent. I believe there are some problems with both puzzles, ...
14
votes
4answers
2k views

Strategy for finding the key to this cipher

A coworker and I are perplexed over this puzzle. We gave up and looked at the answer, but we cannot seem to understand how it works. Can anybody explain? Text version of the above image We've ...
-3
votes
2answers
1k views

Logic-grid puzzle. How do I have to interpret the clue?

There are eight students named Aman, Bobby, Chameli, Deepak, Ekta, Farook, Garima and Harsh in a school. They are in class 6th, 7th and 8th with no more than three students in any class. Each of ...
-4
votes
1answer
260 views

Timetable Planning [closed]

There are 16 seminars with the following durations in minutes: 60,45,30,45,45,30,30,45,60,60,45,30,30,60,30,30 They need to be divided into groups. Each group must have 2 subgroups. The first ...
3
votes
6answers
1k views

Explaining Cheryl's birthday

Relevant link : Cheryl's birthday I understand the solution. But it feels wrong to me, because Albert cannot possibly make the third statement with the information he has at the moment he makes it. ...
-3
votes
1answer
1k views

Working schedule (with explanation) [closed]

Alice, Bob, Chris, Dave, Eric, Fred and Laura used to work in a restaurant 6 days a week, from Tuesday to Sunday (Monday is a day off). Every one works at least for one day, and at least two people ...
-6
votes
3answers
568 views

Cows eat too much [closed]

Cows are always hungry... 70 Cows eat all the plants on a pasture in 24 days. 30 Cows clear the same pasture in 60 days. How many cows are needed to clear the pasture by the end of 96th day?
-4
votes
2answers
187 views

Group of Farmers [closed]

A group of farmers need to harvest 2 farms, one of which is twice the size of the other. They worked half of the first day on the bigger farm. Then they split into two equal groups to work on ...
8
votes
2answers
13k views

Explanation for the “I am whole but incomplete…” riddle?

I saw a riddle: I am whole but incomplete, I have no eyes, yet I see. You can see, and see right through me. My largest part is one fourth of what I once was. What am I? Apparently the answer is: ...
-3
votes
2answers
1k views

What is the purpose of a weird non-linear watch dial that goes up to 100? [closed]

Can anyone tell me what is the purpose of the outter dial of this watch? Notice how the scale is not linear and goes to 100. It can only be rotated counter-clockwise only. This is the only picture I ...
17
votes
8answers
6k views

When to be sure that we have counted all the squares in such problems

My first question: how would one solve such problems (in general)? What should be the general technique? My second question: When to be sure that we have counted all the squares in such problems?
13
votes
5answers
1k views

Why is “trapeze” the solution to this cryptic crossword clue?

I was doing a cryptic crossword this morning and I came across the following clue: Circus equipment has chimpanzee, say at the centre The answer is "TRAPEZE" (confirmed by "check answers"). The ...