Questions tagged [mathematics]

A puzzle strongly related to mathematical facts and objects, or whose solution needs serious mathematical arguments. General mathematics questions are off-topic but can be asked on Mathematics Stack Exchange.

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5
votes
2answers
165 views

Standard Sudoku Specialized with just 2 Primes

A standard 9x9 Sudoku uses the digits 1 to 9. You are only allowed two distinct primes to represent 1 to 9. Find out the minimum number of characters (digits + signs) needed to construct a Sudoku ...
-5
votes
2answers
135 views

Numberless Sudoku with Just a Letter and Symbol Combination

A Standard 9x9 Sudoku uses the digits 1 to 9. You are only allowed to use a single letter(say T) and a symbol of your choice to represent the digits 1 to 9. Rules should be well defined and the ...
9
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3answers
596 views

A Mathematical Discussion: Fill in the Blank

I originally saw this on r/puzzles, and thought it deserved a place here. I have a solution to this puzzle, but it's really long and ugly. If anyone comes up with something simple, please share! ...
5
votes
4answers
866 views

Why did this prime-sequence puzzle not work?

While attacking a recent puzzle (whose solution ended up being entirely different from what I was trying), I was inspired to create a number-sequence puzzle with a sequence $(p_n)$ of primes where the ...
3
votes
1answer
220 views

Happy New Year?

Extend this infinite series by five more terms: 17, 3, 5, 7, 11, 17, 2, 3, 5, 11, 13, 17, 2, 5, 7, 11, 13, 2
0
votes
1answer
115 views

UVC wants to give you a Helping Hand in Solving these Unique Set of Pan digital Fractional-Decimal Relations

Use pure logic and deductive reasoning only. Document detailed steps in arriving at final solution. You can use calculator minimally. $ Given$: Utilizing These two unique set of Pan digital ...
12
votes
1answer
385 views

Infinite Sequence based on Simple Rule

Using one simple rule, an Infinite Sequence has been developed. First 30 terms are given. Can you continue the sequence for at least next Ten Terms? Series continues from top left to bottom right. $...
0
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4answers
6k views

Four boys and four girls

Four boys and four girls go to a movie theater to see a movie. All the boys sit together and all the girls sit together. All the boys and girls are sitting in 8 adjacent seats. After some time, the ...
12
votes
4answers
852 views

Find the three digit Prime number P from the given unusual relationships

$Given:$ P is a 3 digit prime number Q,R,S,T are distinct digits( 0 to 9 ) QRS is a concatenated number $Relationships:$ $P$ = $QRS + T$ = Reverse of $( QRS * T)$ Find P using just ...
9
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4answers
413 views

Breaking Balance (Part C)

For a starting number of otherwise identical coins there are among them TWO IDENTICAL counterfeit coins which are either heavier or lighter than the rest. Using a three-pan balance (described in ...
0
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1answer
75 views

We are Unique Friends. Our Special Squares Share a Common Bond…Figure us out

Use logical deduction only and document your steps in detail. $Given$: A, B, C, D, E, F, M , T are distinct digits(0 to 9). ABC, EBF, DDABC, MCMABC, TBBB are all concatenated Numbers. $...
-1
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3answers
310 views

WAS IT A CAT I SAW? Do Some Detective Work & Catch The Imposters

Carolina County Community Cat Conference is going on at a resort exclusively reserved for Prime Members. Some look-alike impostors, aka cats, have sneaked in. They all wear fancy name tags that ...
6
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5answers
321 views

How to Modernize Student Council

You are the math teacher at a high school and you are in charge of organizing Student Council for the whole school next year. Your boss, the Principal, read a research paper on Student Councils and ...
3
votes
2answers
132 views

Devil in Different Disguises but in Prime Shape…Can you Figure out his Diverse Expressions?

$Given$ $Devil$ goes by $666$ Express him as 1). Sum of all Primes in 3 Different ways using all the digits 0 to 9. Use only + sign. 2). Sum of all Squares of Primes. Use only + and ^ signs. 3)...
8
votes
2answers
564 views

Maximum Result with Digits

You have digits from $0$ to $9$, where you need to use every digit only once, and you have only one operator (multiplication, $*$). You may combine/join digits to create a bigger number as shown below:...
-1
votes
2answers
120 views

Famous Number Displays Dual Cubic Relationships..Figure it out

$Given$: A, B, C, D are all distinct digits. ABCD is a concatenated number $ABCD$ = $A^3$ + $(A+C+D)^3 $ = $D^3+ (A + D)^3$ Figure out this Number and why is it Famous? Also provide ...
-1
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2answers
148 views

Hexagon vs Harry Houdini…Round 1…How did Harry do? Let us Find out

$Given:$ Harry Houdini is Mental Math Magician and top Math Wizard at Hexon..one of the top cryptographic companies in the world. They have deployed Passwordless super smart secret system to ...
6
votes
5answers
1k views

Long digital sequence. 16xxxxxxxxxxxxx61

Find the digital key and very simple method to unlock the long digital sequence 16xxxxxx61 Additional clues: Eeryday one clue will be given till problem is solved Day 1: Bounty Day 2: My code is ...
6
votes
1answer
351 views

The Most Powerful Number

A power-full number is defined as a number with $n$ amount of non-zero digits $D_x$. The number takes the form $D_n$&$...$&$D_2$&$D_1$. The digits in a power-full number satisfies the rule ...
1
vote
2answers
94 views

Math quiz from a book [closed]

A student took some exams. The arithmetical average of his grades is 25. He takes another exam today and he gets a 30, so the arithmetical average of his grades becomes 26. How many exams did he take, ...
5
votes
2answers
234 views

SAD!!!…System Access Denied..you got three minutes to input three digit passcode

Given Hexagon is super secret system with varying levels of access. Users do not have to remember any password. They just have to answer the questions posed by Hexagon strictly in the allotted time. ...
1
vote
1answer
81 views

Lady Luck Powers Up Every Member to Sum Upto Non-Prime Number. Who am I?

$Given:$ UV, WX, UVCUVWX, are concatenated Numbers. U, V, C, W, X are distinct digits ( zero to nine ). $Relationship:$ $UVCUVWX$ = $U^7 + V^7 + C^7 + U^7 + V^7 + W^7 + X^7$ $Clues:$ 1) UV ...
8
votes
1answer
152 views

These Two Cubes are The Only Ones That Are All Pure Prime..name them

Given: CU and BBUE are concatenated Cubes with all prime digits B, C, U, E. Which are these two Unique Cubes?
13
votes
6answers
329 views

Pulling Apart a Jigsaw Puzzle

Assume you have a jigsaw puzzle that is also a tessellation. This means every piece has an identical shape and can be assembled into a 2D pattern that fills the plane with no gaps. Such a jigsaw ...
1
vote
1answer
169 views

Be a Wizard..Find the missing digits of this 41 digit Humongous Palindromic Square!

Absolutely No calculators or computers. Only Simplest Method for finding the missing digits will be accepted as the right answer. Given: The square of this 21 digit number $ 229 359 782 235 085 ...
8
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2answers
257 views

How many times does the earth rotate per year?

Assuming there are exactly $365$ days per year. How many rotations about its axis does the earth make in one year?
1
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3answers
443 views

Palindromic Pan digital Special Square wants you to reveal its Root

All you need is just Mathematical Logic and few minutes. No calculators... no computers. Concise Logic based answers are the preferred choice. Given: Palindromic Pan digital Perfect Square ...
2
votes
1answer
99 views

Puzzling Palindromic Year with Pleasing Palindromic Expression.. Please find them

No computers, calculators or searches. Given: The number is a Palindromic year. $PQ$ is a concatenated number. $ U , V $ are two distinct positive integers Expressed as $ PQ ^ U + PQ ^ V + ...
5
votes
3answers
221 views

Find this Unique UVC Palindrome ( ignoring signs and decimal) from Given Fractional Relationship

Given: U, V, C are three distinct digits ( 0 to 9 ). UVVVV and CVVVV.U are concatenated numbers. Dot “.” Stands for decimal. Relation: $UVVVV/C= CVVVV.U$ Find U, V , C
4
votes
2answers
230 views

Simple Maths Riddle 6

A sixth riddle! There's a function just (reserved) for me though you need three of me to complete it. Don't simplify (me) when the top's much larger; I'll ...
3
votes
2answers
152 views

Can you express this orderly Palindromic Devil in strict ascending Pandigital form?

Given: Devil as you know is $ 666 $ Using digits 1 to 9 in strict ascending order and only three mathematical signs ( +, -, /, x ... of these are allowed), write the Pandigital expression $ 666 = ...
0
votes
2answers
86 views

Uvc with Lots of Magic… Enjoy the Show!

Puzzling Weekend! UVc is back again with Lots of Magic... Enjoy the Show! Given: LOTS is being multiplied by F to yield MAGIC. Digit 0 to 9 are all represented by ten different letters in this ...
7
votes
1answer
285 views

Simple Arithmetic Puzzle 7. Or is it?

The Arithmetic Puzzles are finally back! The break I took was longer than expected... Let's start easy then. \begin{align}6\times8&=72\\10\times9&=6\\1\times1&=1\\18\times69&=\,?\...
0
votes
2answers
108 views

Number of Days in a Year with Consecutive Perfect Squares

Given: Number of Days in a normal Year To Do: Express it in two different ways utilizing Squares of consecutive positive numbers.
3
votes
2answers
134 views

Find the values of U, V, C based on the given relationship…useful for upcoming puzzles

Given: U, V, C are 3 distinct digits..values can vary from 1 to 9. CU is a concatenated number Solve for U,V, C from the following relationship: $U^V$ X $V^U $ = $CU $ This will give some basis ...
8
votes
4answers
906 views

Mathematical puzzle: ten digit lock number

A mathematical professor set his lock number, he used mathematics so he would remember the ten digit code. He used all of the digits from 0-9, every digit only once. In his mind the first two digits ...
38
votes
8answers
5k views

Who is our nearest planetary neighbor, on average?

Assume that the planets have circular orbits centered on the sun. Assume that the radius of the orbits is 0.39, 0.723, 1, and 1.524 for Mercury, Venus, Earth, and Mars. Assume also that there are no ...
2
votes
2answers
182 views

Cathy’s Composite party is powered by three Prime Pals. Can you find them?

Given: A, B, C are 3 distinct primes. Find the smallest composite number Y that satisfies the relation: $ Y = A ^ C + B ^ B + C ^ A $
11
votes
3answers
630 views

Five Powers of Fives Produce Unique Pandigital Number…Solve for X..Tell me Y

Given: Y is a Pan-digital Number (no zero, 1 to 9 only) ending in 3. Pan digital number consists of all 9 digits 1 to 9..each digit occurring only once as is the case here. Last digit is given as 3 ...
1
vote
1answer
85 views

After seeing my 16xxxx16 sequence puzzle, my Younger sibling wants to get into the act and give a little puzzle of his own

In our Reptand prime family, as you know, everybody has our own signature Cycle length. My younger sibling unit has shorter cyclic period and he wanted to create little puzzle for you. He truncated ...
5
votes
2answers
135 views

Prime turns into Perfect Cube, if you reverse its digits and subtract…What is the number

Given: 1) I have more than one digit. 2) Reversed number is subtracted to give at least 2 digit number which should be a cube. 2) you don’t even need a calculator to figure me out. Who am I?
2
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1answer
85 views

Composite Cat Cannot divide its immediate lower neighbors factorial without leaving a remainder

Find this unique composite cat given the information in this title.
0
votes
1answer
101 views

Identify the rule and find the missing number

The following sets of numbers are connected through a common rule/patern. Find the missing number(?) $(255,153,51x)(153,0xx,51x) = 669900$ $(255,204,51x)(204,51x,51x) = 339900$ $(153,153,...
1
vote
2answers
97 views

Unravel this simple cryptic Unique NUMBER relationship

Find GC ...it is a concatenated number Given: N + U + M + B + E + R = GC
9
votes
3answers
1k views

Find the area of the rectangle

The image below shows a half circle, and a rectange DBFE. Your task is simply to calculate the area of the rectangle, based on the information given in the image.
8
votes
1answer
679 views

A B C in close knit relationship.. Who are they?

Find these closely knit numbers examining their relationships. A, B, C are distinct positive integers. AB, AC are concatenated Numbers. Given: 1 / AC = 0.0BC0BC0BC...... 1 / BC = 0.0AC0AC0AC......
2
votes
3answers
2k views

Should I take the antidote? [closed]

A new disease has been discovered in the world, it is called Blue. Statistically 1:1000 people in the world has it and it makes your whole skin blue in a few weeks after getting the disease but not ...
7
votes
1answer
373 views

It is as easy as A B C, Figure out U V C from the given relationship

Given $ U, V, C $ are three distinct digits, figure them out from the following relation: $$ \overline{CCC} = \overline{UVUVUV} \div \left ( \overline{UV} \times \overline{UV} \right) $$
0
votes
1answer
89 views

Find the missing parking space number [duplicate]

Each space in this parking area is numbered. The parked car covers one of the numbers. What is the number? For reference, the parking numbers are $16,06,68,88,X,98$ where $X$ is the hidden number.
13
votes
5answers
2k views

Find the unknown area, x

The image below shows one large rectangle, with smaller rectangles inside it. Your task is simply to calculate the area of the red rectangle, marked with an x. Note that I have deliberately made the ...