Questions tagged [calculation-puzzle]
A puzzle that involves numerical calculations, such as multiplication and addition. Use with the [mathematics] tag.
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Why aren't 59 L tiles the answer to this problem? [closed]
4*(1+3+5+7)=8^2
4*(sum of odds from first to kth odd number)=area of a square region=4*k^2
k-1 is the number of Ls.
You can solve the 10x12 problem via considering 10x10 and the extra 1x2 not added ...
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Before the Common Era
This is part 39 of the puzzle series Around the World in Many Days. Each part is solvable on its own.
Dear Puzzling,
The grid on the left-hand side is a KenKen puzzle. Fill the grid so that every row ...
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18
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3
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Sums in a (very small) box
This puzzle is part of the Monthly Topic Challenge #14: Think inside the (very small) box!.
Place the digits 1 to 9 in the box below in such a way that in each row, each column and each diagonal, one ...
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Figure Out The Language: Min
Imagine there is a programming language in which you can only evaluate expressions. Expressions have operators and constants.
There are three types of constants.
Numbers - Any number from 0 to ...
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Find the ciphering method 2
Link to the entire series.
The message:
3, 53, 48751, 9247757, 294914580539
The answer is a 13 letter word: UNDERSTANDING
Hint 1:
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Find the ciphering method using deciphered message
Link to the entire series.
Ciphered message:
...
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Decipher a long sequence of numbers
51699624576811268526783109824167925197245652924177251787241782538786302873119768312852668312686625268245686752824473216878253830287925175273039778250852831287672527245665263006725397251762529312811498
...
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Find the largest number with unique digits, that is divisible by each of its digits [duplicate]
Find the largest number with unique digits, that is divisible by each of its digits.
For example 132 has unique digits and is divisible by 1, 2 and 3. But it is not the largest such number. Can you ...
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Help a woman from ancient Rome find out how her husband is doing
Let's go back 2000 years. A woman named Valeria received a strange message from her husband Claudius who is a frumentarius.
The message:
...
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Operator! Some Product!
Happy Venndredi all,
A relatively straightforward one! The three overlapping ellipses form seven curved regions and there are seven tiles. Your task is to place exactly one tile per region so that ...
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Combine 1,3,3,7 to get 10
I tried lots of combinations but could not find a solution. Each number has to be used exactly once, the allowed mathematical operators are
Addition: +
Subtraction: -
Negation: (unary prefix) -
...
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What does this mathematical operator do?
The solution to this puzzle is one I came up with when working on this puzzle: What is the answer of this math puzzle?
For two natural numbers a,b, can you figure ...
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What is the answer of this math puzzle?
One of my friend brought this simple-looking math puzzle to me, but it was harder than it seems.
I tried several ideas including simple arithmetic operations, and even considering base-n.
...
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Nuts and screws
Imagine that you are given a box with n nuts and n screws. Each screw have different size (diameter) and on each screw there is ...
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1
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A and B don't know their own values
() isn't used mathematically in this puzzle. () means that whatever is inside should be evaluated in the most suitable and ...
2
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1
answer
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Is Sumplete always analytically solvable?
I am stuck here at Sumplete.
I have tried looking for numbers that must be used/must not be used using https://combinationsumcalculator.com/ and all of them are either not used in all combinations (...
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Three clocks problem
Three clocks which show the times for three different time zones are hanging on a wall. The length of their minute hands is the same - but not the lengths of their hour hands. The lengths of the hour ...
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Three boats problem
Three boats are sailing on the ocean. The three boats form the corners of an equilateral triangle. Boat 1 heads southwards with a constant speed of 10 kn, boat 2 heads westwards with unknown constant ...
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Is there an answer to this 'turning my fan off' puzzle?
I have a ceiling fan with 4 states. The states always go in the order of off, high, medium, low, off. A cord pull will change the state.
One pull of a cord to turn the fan to the off state from the ...
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An animal climbing something (forward/backward slide): is there a generalized solution?
A snail is at the bottom of a 30 foot well. Every hour the snail is
able to climb up 3 feet, then immediately slide back down 2 feet. How
many hours does it take for the snail to get out of the well?
...
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Cable with mixed wires
Let's say you have a cable that has n wires. Each wire on the left side corresponds to one wire on the right side. However you cannot distinguish between the wires ...
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Do puzzles like "write 120 using four 8" have a specific name?
Here on puzzling SE there is the category "calculation puzzle", but it's very broad. I'd like to know if somebody gave a specific name for such puzzles.
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Answers all, boob, X
A four-letter name is encoded A=0 to Z=25. Find a name that satisfies:
The sum of the integers answers all,
their product is like a boob,
and their range is X.
Order the integers by increasing ...
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Fill in the blanks with 1-9: ((.-.)^.)*..+.-.-.-.= 100
This is a math puzzle asked by a teacher of mine that I can't figure out. The puzzle is to fill in all blanks with digits 1-9, using each only once, to equal 100. The equation is as follows:
(dots are ...
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Lengths of sides of a right-angle triangle [closed]
Let's have a right angle triangle. The sides have lengths equal to rational numbers. The area of the triangle is equal to 39, the length of the hypotenuse is 31.3 and the difference of the other two ...
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Four ones and four zeros
Which is the smallest natural number that can not be expressed in base 2 with precisely four ones and four zeros using the four basic arithmetic operations, exponentiation, concatenation, brackets, ...
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Ernie and the Chance to Save a Beautiful Relationship
I should have smelt a rat when Ernie invited me to an event at the local club rooms, because when I asked why his wife was not attending, he replied that she had another engagement for that night. “I ...
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Equilibrium of differences
There is a subtraction equation written on the board, with three digits minus three digits, and the first digits both fixed. Alice and Bob need to fill in the remaining 4 digits (A~D below) using 4 ...
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Multiple Line Lengths around 8 triangles
The image below contains 8 triangles each having side length 6.
Inside each triangles are three numbers indicating lengths of 3 lines that are wrapped around the triangle without gaps.
Numbers range ...
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1000 digit sum calculation puzzle
I have 7 numbers that add up to the same value as the sum of the base 1000 digits of the product.
Here are the numbers:
86, 203, 296, 395, 401, 407, 913
The first part of the puzzle is to understand ...
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Time (and a place) for an odd-one-out puzzle
This puzzle is part of the Monthly Topic Challenge #6: Is it really that [time] again?.
It is a tough task to create an 'odd-one-out' type puzzle whose solution lacks any ambiguity at all - it is all ...
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Trust me: you do not want to go down this road with me
Every cell has a digit from 0 to 9 or one of the four operation symbols +, −, ×, and /, signifying addition, subtraction, multiplication, and division respectively.
No digit appears more than once in ...
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Money in a piggy bank [closed]
In the attic of his house a man found an old piggy bank with twelve cents inside. He called two of his friends to come and see the antique piggy bank and asked them to put more money into the piggy ...
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Nifty Nines Impossibility Puzzle
Could someone please provide me the solution to this puzzle:
99 + 9 = 9?
Professor Otto Doppelganger was one of Europe's leading puzzle experts. In the summer of 1899 he invented the Nifty Nines ...
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Tile and Error - When Seven Ate Nine
Ok folks, so the three overlapping ellipses form seven curved regions. Your job is to place all seven tiles so that each region has exactly one tile and each ellipse adheres to the corresponding ...
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Create 76 out of 1,2,3,4
You can use +,-,*,/,^,! and sqrt operations (no concatenation) and all numbers must be used once and only once.
for example, 75 can be made by $3×(4!+2-1)$ and $81=(2-1)×3^4$
I've been trying to reach ...
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Stuck on hard Kakuro
I‘m stuck on this Kakuro. Does anyone have any hints how to proceed? Thanks!
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Sergeant Sequence brings in the analysts
This puzzle is part of the Monthly Topic Challenge #5: On-and-onograms
"We've intercepted another message, Chief."
"Good work, Sequence. What does it say? Where is Terne now?"
The ...
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What is the biggest number you can make with 6 9s?
What is the biggest number you can make with 6 9s?
These are the allowed operators:
Subtraction
Addition
Multiplication
Division
Factorial
Exponents
Square root
Floor and Ceiling functions
Arbitrary ...
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2
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Trapped with a number puzzle
A family of your most hated Nggyupnglydown tribe has turned you into a vampire and trapped you in a chamber with a screen and some buttons on it, and you have to enter the code 4, 8, 15, 16, 23, 42 (...
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Reviving the Ruins of Number Kingdom
The great wizard Factorial surveyed the empty buildings with an
ever-increasing sense of dread. The staff of recursion he held was
incredibly powerful and could do great damage in the wrong hands. In
...
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Make e using 1, 2, 3, 4, 5, 6, 7, 8, 9
Can you make $e$ with the digits 1, 2, 3, 4, 5, 6, 7, 8, 9?
You can only use the digits once.
The allowed operators are listed beloẉ.
Addition
Subtraction
Multiplication
Division
Square root
...
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Make the numbers 1-100 using 1,7,3,4
I made this puzzle myself. As the title says, you must make the numbers 1 to 100 using the numbers 1,7,3,4 - in that order. All numbers must be used. The allowed operators are below:
Addition, ...
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What extra number did I form?
My friend and I are each trying to form the integers from $0$ to $100$ using the numbers $2, 3, 8, 9$. We are only allowed to use the five basic operations: addition, subtraction, multiplication, ...
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How many digits does $7^{100}$ have?
I'd like to estimate $7^{100}$ without using these new-fangled computers everyone is talking about, but I think I need your help.
Please estimate $7^{100}$ without the use of a computer. My friend ...
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The computer can't do anything I couldn't do with pen and paper
If you want to know how much $3^{100}$ is, you can just type it into a computer and it will spit out a really big number. But that is no fun. The task is to estimate $3^{100}$ with some computation ...
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Can you Avoid the Spear-Wielding Gladiator?
You are trapped in a circular coliseum, and a gladiator with a spear is chasing you. You can't defend yourself, but you can run faster than the gladiator.
You run at 11 feet per second, and the ...
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A Pubular Puzzle
Try to make sense of the puzzle below.
Circle1, circle2, circle3, circle4, circle5, circle6 and circle7 have radius r1, r2, r3, r4, r5, r6 and r7 respectively and periferi p1, p2, p3, p4, p5, p6 and ...
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