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

4
votes
1answer
348 views

Solve this puzzle. I created for my friend for FUN :)

My friend is very good at puzzles. so i thought of creating one by myself and try to see if he can solve. Finally I succeeded and he gave up. Interested people can try. Hint: use all four arithmetic ...
1
vote
1answer
193 views

What is the value of X?

24 6 63 132 4 14 23 x 17 The answer is either : 21, 14, 3 or 2
9
votes
4answers
3k views

Find out the correct number

Find out the correct number to replace the question mark. Source: Beijing Aidi International School summer test (2018-08-21). Author: 坦途国际教育
2
votes
1answer
64 views

What is the expected result? [duplicate]

I found the following puzzle through social media websites, What is the expected result? It seems to be easy. But, it needs concentration.
2
votes
6answers
222 views

A Maximising Puzzle Gift for my Girlfriend and I's 28th month Anniversary

The 28th of december 2018 will exactly be the 28th month since I date my fabulous girlfriend, by this time she'll be 18 years old. Here's a puzzle I'll give her this day : Classical part Maximize $...
3
votes
2answers
738 views

make this sum using only +

A bit of a speed question this, first correct answer gets the check. Although you are allowed to use computers, it might be quicker not to. By placing only $+$ signs between some of the numbers on the ...
4
votes
2answers
639 views

Use 2, 0, 1 and 8 to make 71

Use all and only the digits $2,0,1,8$ once each to make the number $71$. Allowed operations; anything not on this list is banned: $+,-,\times,\div, ()$ (parentheses and/or choose function) ...
14
votes
6answers
2k views

Use 2 0 1 and 8 to make 67

Use $2$ $0$ $1 $ and $8$ to make the number $67$ RULES You must use all 4 digits. Only the digits 2, 0, 1, and 8 can be used. You can make multi-digit numbers out of the numbers. Examples: 20, 82, ...
6
votes
8answers
483 views

Make $1,\dots,15$ using $3, 9, 9, 9$

This was inspired by many puzzles that use three/four numbers to create other numbers. I chose these numbers in particular because of this post. Can you find a way to make all the natural numbers ...
2
votes
2answers
131 views

Use math symbols to produce 6 [duplicate]

How can we get (6) from these numbers? $2$ $2$ $2 = 6$ $3$ $3$ $3 = 6$ $4$ $4$ $4 = 6$ $5$ $5$ $5 = 6$ $6$ $6$ $6 = 6$ $7$ $7$ $7 = 6$ $8$ $8$ $8 = 6$ $9$ $9$ $9 = 6$ $12$ $12$...
1
vote
2answers
154 views

Simple Math Problem #3

Previous Puzzles(Not linked to this one): Simple Math Problem #1 and Simple Math Problem #2 Prove the equation: $-6439832+ = 9$ $-$ and $+$ are there just to tell that you can use only these two ...
4
votes
5answers
2k views

What is her real age? [closed]

He : What is your age? She : 35 years old, ignoring the intervening Saturdays and Sundays. What is her real age?
4
votes
2answers
220 views

Find the missing number (triangle)

Find the missing number (triangle) Options: 9 8 7 10 Please write the logic also.
3
votes
2answers
68 views

Puzzle #2: Prosecutor's Pathway

This one prosecutor has a very busy schedule. However, although his business can get busy, he is a lawyer faithful to his job, which is why he spends some weekend time at his private law firm. Since ...
2
votes
3answers
76 views

Puzzle #1: Love In the Air

A couple that were just engaged decided to have their wedding in a hot air balloon. The biggest problem that the couple has is how many guests that they can invite. There are three different types of ...
6
votes
3answers
480 views

Pizzle - Will you ever show up, Rick?

NB: Pizzle = Puzzle + Riddle Chapter 1: Let's start You can see me, but you can not catch me I'm lightweight, but I could lift you up easily Chapter 2: The First Piece I'm that one, which ...
1
vote
2answers
302 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
163 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
231 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
97 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 ...
5
votes
1answer
194 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 ...
4
votes
1answer
294 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
481 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
382 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
562 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
453 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
289 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
66 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 ...
4
votes
1answer
139 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
446 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
142 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
403 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
179 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
93 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
215 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
142 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
153 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
353 views

Elementary vowel equations

Challenge Solve the following equations by converting to standard form (see below): ** eeeeee = aeeeeiiiouu ...
2
votes
2answers
183 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
329 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
130 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
107 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
265 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
577 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. ...