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A puzzle that involves numerical calculations, such as multiplication and addition.

1
vote
2answers
264 views

A Secret Math Society

I was about to try to join the famous Math club at my school when I stopped to hear my classmates doing the same. I didn't know that newcomers had to take a simple test to be qualified until my they ...
5
votes
1answer
144 views

Another pattern puzzle with a twist…well, not quite so

What are the next two terms of the following crazy sequence: I, h, 6, 9l, 52, 9E, 6h, __, __ ?
4
votes
1answer
223 views

The wine paradoxon

You're a fellow salesman who happens to have to sell a barrel full of wine. The barrel has a capacity of 5 Litres. Unfortunately, your apprentice is a wine lover and steals some wine each night, ...
0
votes
1answer
91 views

double the stone puzzle

Story: I've x number of stones. On my way, I will cross three wells. When I reach a well, then I will throw y number of stones ...
4
votes
1answer
168 views

How to choose the next board in the 8-puzzle?

I hope to have your help to solve the problem I am facing. I'm trying to make an 8-puzzle solver but I'm in doubt about how to select the next board, from the one they have already given me. Below I ...
1
vote
0answers
158 views

M Professors and N dishes

Suppose 'M' number of professors have to guess 'N' number of dishes on a roulette menu offered by a restaurant. This restaurant has a special "roulette menu" with N items, in which you choose a menu ...
5
votes
4answers
473 views

New Arithmetic Operator?

So my British friend proposed a new operator, but he wouldn't tell me how it works. He told me if I could figure it out then I could know. He's not very nice. Anyway, help me figure it out? 1 🎫 1 =...
3
votes
1answer
364 views

I have more than one face, but I have no eyes. I roll out of hand during multiple tries

Riddle me this: I have more than one face, but I have no eyes. I roll out of hand during multiple tries. I very much often do not roll alone; I have a partner, who like myself, ...
8
votes
5answers
1k views

Streets Puzzle and Positions

The diagram below shows the street map of a city. If three police officers are to be positioned at street corners so that any point on any street can be seen by at least one officer, what are the ...
8
votes
3answers
555 views

Order matters twice

Mr. Accurado, a keen and sharp eyed professional thought of starting his special assignment at few seconds past midnight. However due to a distraction- which lasted for less than a minute - he could ...
2
votes
6answers
1k views

How cold is too cold? [closed]

On a day during a severe winter, somewhere in cold countries, I watched a weather report on a television. The report showed that on that particular day the temperature was 0° ....but due to some ...
8
votes
1answer
443 views

Magic Square Puzzle

Construct a 5x5 magic square. 1- Numbers from 1 to 21 can be used. 2- Sum should be 55 (Horizontally, Vertically and Diagonally) 3- Any 4 digits from 1 to 21 can be repeated only once. 4- The Numbers ...
27
votes
5answers
2k views

Making Things Difficult

An entry in Fortnightly Topic Challenge #35: Restricted Title 1. Factoring the Time Think fast! If you're looking for meaning, these clocks have some for you. Keyboards are Disgusting Gunky ...
7
votes
2answers
281 views

Houses and Telephone #s

There are 16 houses consecutively numbered 1-16. All houses have 7-digit telephone numbers, numbered consecutively, in the same order. For example, if house #3's phone number is 1111111, house #4 will ...
1
vote
0answers
65 views

3 Horses out of 25 Horses [duplicate]

You've got 25 horses and you can host races in groups of 5. You don't have a stopwatch, obviously. Then what should be the minimum number of races that you should be conducting so as to ascertain the ...
3
votes
1answer
131 views

An Incorrect Summary of a Twenty-Two Day Tour

After a long but rewarding life in an office cubicle, Sally the office worker became Sally the retiree. Feeling unfulfilled, and with ancestors who had served admirably in the Navy, Sally the retiree ...
9
votes
2answers
413 views

How old are Charlie's pets?

Last year at a picnic, Charlie told Julie's daughter the sum and the product of the ages of his dog and two cats, but she guessed the ages incorrectly. This year, he gave Steve's daughter the same ...
2
votes
1answer
141 views

Need little help

Note: Sorry, this puzzle almost similar with the last question: The main purpose of this QUESTION is: To know what types of this puzzle is exactly. It is still can be solve if I remove the most ...
11
votes
1answer
388 views

An Incomplete Puzzle

I'm sorry to offload some of my work as the puzzle creator on to you solvers. (No, I'm not.) At least there's only one clue missing, right? EDIT: When the puzzle is ready to be solved, there will be ...
2
votes
2answers
178 views

What are the chances on watching the clock? [closed]

This is a relatively straightforward little puzzle, but the answers are somewhat unintuitive or can prompt a new perspective. It might be an interesting little puzzle for a probability teaching ...
-5
votes
1answer
90 views

Surprisingly(not literally) easy one? [closed]

What are the next two numbers in the following sequence: 0, 1, 4, 18, __, __. Please explain your logic.
5
votes
3answers
1k views

A pokemon puzzle [closed]

You have recently caught N Pokemon and you also have M Pokemon candy bars. You can evolve any of your Pokemon by paying X candy bars. Alternatively, you can sell any of your Pokemon for a price of ...
8
votes
3answers
2k views

Fully confused calculation

The sum of a three digit number (ABC) and another three digit number (DEF), where DEF is obtained by thoroughly shuffling* the original three digits of ABC, is 1000. Then, find all possible such pairs ...
2
votes
1answer
213 views

Extension to The grazing cows of Sir Isaac Newton

There is an earlier question, The grazing cows of Sir Isaac Newton, which says: Sir Isaac Newton's book "Arithmetica Universalis" contains the following famous puzzle: In $4$ weeks, $12$ ...
3
votes
1answer
135 views

systematic number removal [duplicate]

The whole, natural numbers 1 through 50 are written on a board. The following operation is performed 49 times: select any two of the numbers on the board and write the absolute value of their ...
-1
votes
1answer
148 views

Fuzzy's Fizzy Dilemma

Fuzzy the Fuzzball's friends was going to the Fuzzball Festival, and of course he went along. While there, he saw the most curious display. The booth was displaying brand new types of Fuzz. There was ...
8
votes
2answers
352 views

Elementary vowel equations

Challenge Solve the following equations by converting to standard form (see below): ** eeeeee = aeeeeiiiouu ...
2
votes
2answers
180 views

How can i move forward (kenken)

I can't seem to find a next step to logically come to without guesswork. Any ideas on how to move forward?
3
votes
3answers
324 views

Dividing money in school [closed]

A businessman instituted an annual award in a city school, with part of the award given to the school itself to improve its facilities. It was stated that if a student from a wealthy family were to ...
-1
votes
1answer
129 views

Water Difference

While solving a puzzle, I misinterpreted the whole thing and ended up creating a new harder puzzle. Here it is: You have 2 cups filled with water, cup A is 5oz and cup B is 3oz. How can you get one ...
-3
votes
1answer
105 views

Calculate cost of excess water consumed [closed]

100 Liters of water is available equally in a month for consumption among 5 members @ 1 dollar per liter. If some members don't use their own available 20 liters, it can be used by the others at the ...
25
votes
3answers
1k views

A game of multiplication and addition

Carol is playing a game with Alice and Bob. She secretly chooses two integers between 1 and 10 and gives the sum to Alice and the product to Bob. After some time, the following discussion occurs: ...
3
votes
1answer
239 views

Analyzing Single-Elimination Tournaments

I know there are many questions/answers about single elimination tournaments out there, but I wanted to approach this question in a more holistic way. For a single-elimination tournament with N ...
5
votes
3answers
563 views

Can you find the value of the question mark$\color{red}?$

Puzzle: Find the value of the question mark $\color{red}?$. $$(2, 13, 47)$$ $$(5, 7, 19)$$ $$(8, 1, \color{red}?)$$ Hint 1: $\color{red}?$ is a prime. Hint 2: $\color{red}?$ is a cyclops. ...
2
votes
1answer
216 views

The A-B chocolate puzzle!

Imagine you have 2 types of chocolates (A and B). You randomly pick up two chocolates at once from your bag in a specific pattern. If the same type of chocolates come out, you give them both to your ...
2
votes
3answers
151 views

Sufficient time to fill the bucket [closed]

Suppose that we have a pierced bucket, and that the hole empties the bucket in four hours. We place the bucket under two faucets at the same time. If the bucket weren’t pierced, the first faucet would ...
6
votes
3answers
896 views

What is the next number to appear in this sequence?

$1, 1, 0, -2, 4, 18, 328, 107638 ,?$ This problem can be complex, use your imagination. Hint: Hint 2: Hint 3: Hint 4: Hint 5: Hint 6: Hint 7:
9
votes
5answers
3k views

How Will You Get 100 Fruits in Rs.100?

Source: https://www.bissoy.com/720699/ For Rs. 0.5 you get 1 Cherry. For Rs.3 you get 1 Orange. For Rs.5 you get 1 Watermelon. Your mother told you to get 100 fruits for Rs.100. ...
5
votes
3answers
2k views

Mathematics IQ puzzle, solving puzzle by looking at neighboring digits [closed]

Can anyone solve this puzzle? I have tried many times but I could not find any symmetry or sequence. \begin{array} {|c|c|c|} \hline 3&25&5\\ \hline 16&9&6\\ \hline 125&36&18\\ ...
4
votes
8answers
7k 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 ...
2
votes
2answers
523 views

Find the next number in the sequence below?

Find the next number in the sequence below: 298 209 129 58 ? Source: Briddles.com
2
votes
9answers
1k views

How to use the numbers 3, 5, 6, and 7 to get 100? [closed]

Any mathematics symbols and processes to use the numbers 3, 5, 6, and 7 once each to get 100.
48
votes
8answers
14k views

The Cucumber Paradox

Suppose you have 100 lbs of cucumbers and these cucumbers consist of 99% water. You decide to leave the cucumbers in the sun for a while until they consist of 98% water. You bring the cucumbers back ...
-12
votes
2answers
207 views

What will be the answer?

What is the answer of the given puzzle? Please send solution. ...
5
votes
3answers
495 views

Find the value of the addition of dice [closed]

Given these: Find the rule, and provide the answer to "?" (the last row). EDIT:Even though "+" denotes addition, it should not be taken in a tradition sense. The positioning and pattern could affect ...
7
votes
1answer
1k views

Find number by solving the pattern

I need to solve the pattern in given format 98 | 54 | 78 7641 | 3120 | 5402 714 | 494 | 726 ...
7
votes
3answers
209 views

Integers around a circle with consecutive pairs differ to a square

Inspired by this puzzle : Integers around a circle with consecutive pairs adding to a square The integers 1 to 50 are placed around a circle in such a way that the difference of any two of them which ...
4
votes
2answers
2k views

How many Donuts? [closed]

Three friends went on a camping trip and on the way they bought N donuts 🍩. They put them in their tent 🎪, and went swimming 🏊. One of them came and divided the donuts in to 3 equal parts, fed ...
4
votes
1answer
278 views

Magic: the Gathering Challenge: Getting Stuffy In Here

first time posting a puzzle in a while, thought I'd bring back some MtG related puzzles. Enjoy! BACKGROUND: The usual magic rules apply here. Please be explicit in mana usage in your solution ...
5
votes
1answer
201 views

Replacing the chip problem [duplicate]

There are $13$ white, $15$ black, $17$ red chips on a table. In one step, a person may choose $2$ chips of different colors and replace each one by a chip of the third color. Can all chips become the ...