**566 calculation-puzzle questions.**

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 $...

The following is a type of logic / math puzzle I've yet to see on this site. I feel it belongs because the kernel of this problem can be reworked into other puzzles.
$N$ pirates find themselves ...

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 ...

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

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 ...

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 ...

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, ...

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)
...

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

Lisa gets picked up from work by her husband at exactly 4 pm every day.
One day Lisa finished work half an hour earlier and started walking to meet up with her husband. She met her husband on the way, ...

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 ...

He : What is your age?
She : 35 years old, ignoring the intervening Saturdays and Sundays.
What is her real age?

$1,20,171,?,9625,57756,288775$
Please find the missing number in the series.
I have already tried with squares, cubes and progressions but couldn't find the problem.

Find the missing number (triangle)
Options:
9
8
7
10
Please write the logic also.

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 ...

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 ...

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 ...

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 ...

What are the next two terms of the following crazy sequence:
I, h, 6, 9l, 52, 9E, 6h, __, __
?

How to solve this puzzle?
This puzzle is taken from the book The Ultimate IQ Test Book by Philip Carter and Ken Russell.

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, ...

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 ...

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 ...

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 ...

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, ...

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 ðŸŽ« 1 =...

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 ...

I published a sequence that seems difficult to the general public, so I've thought of posting it here. It has a very simple logic (language independent). Can you figure out the next number?

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 ...

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 0Â° ....but due to some ...

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 ...

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 ...

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 ...

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 ...

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 ...

Engines numbered 1, 2, ..., n are on the line at the left, and it is desired to rearrange(permute) the cars as they leave on the right-hand track. An engine that is on the spur track can be left there ...

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 ...

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 ...

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 ...

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 ...

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
...

What are the next two numbers in the following sequence:
0, 1, 4, 18, __, __.
Please explain your logic.

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, $12$ ...

Create all numbers from 0-100 only using 1,2,3,4 and 5. No repeats and you have to use each number. Also, you can use any operation. I've only gotten to 50 by pure brute force. I think that this might ...

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 ...

Sir Isaac Newton's book "Arithmetica Universalis" contains the following famous puzzle:
In $4$ weeks, $12$ cows graze bare $3\frac13$ acres of pasture land, and
in $9$ weeks, $21$ cows graze ...

This is not a very difficult problem, but it seems that it hasn't been asked here.
It's one of my favorites, so here we go:
I am twice as old as you were when I was as old as you are.
When you ...

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 ...

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 ...

- mathematics
- logical-deduction
- formation-of-numbers
- pattern
- number-sequence
- lateral-thinking
- word-problem
- geometry
- optimization
- story
- number-theory
- magic-the-gathering
- riddle
- combinatorics
- no-computers
- arithmetic
- enigmatic-puzzle
- computer-puzzle
- cipher
- probability
- open-ended
- alphametic
- algebra
- visual
- strategy

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