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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.

10
votes
6answers
797 views

Why is this Simple Puzzle impossible to solve?

Connect each red circle with each black circle by drawing a line and the lines should not touch. From each red circle, 3 lines must be drawn which connect red circles with black circles, but the lines ...
-1
votes
1answer
81 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 ...
1
vote
2answers
106 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)...
11
votes
3answers
762 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 ...
1
vote
3answers
244 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 ...
0
votes
2answers
107 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 ...
5
votes
5answers
289 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 ...
6
votes
1answer
318 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
votes
2answers
145 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 ...
1
vote
2answers
82 views

Math quiz from a book [on hold]

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, ...
0
votes
2answers
69 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
141 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?
5
votes
2answers
210 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
3answers
429 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 ...
4
votes
3answers
194 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
198 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 ...
0
votes
2answers
74 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
276 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
105 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
118 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 ...
13
votes
6answers
278 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 ...
2
votes
0answers
145 views

Can you Crack Cohen Family’s Cryptic Codes?

Cohen family of four ...each have their own single numeric code to generate first level access to the system. Before first level access is granted, system displays any one of the 4 single digit codes. ...
3
votes
2answers
147 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 = ...
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 + ...
1
vote
1answer
163 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 ...
2
votes
2answers
180 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 $
1
vote
1answer
81 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 ...
11
votes
3answers
617 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 ...
2
votes
1answer
83 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.
5
votes
2answers
131 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?
1
vote
2answers
92 views

Unravel this simple cryptic Unique NUMBER relationship

Find GC ...it is a concatenated number Given: N + U + M + B + E + R = GC
8
votes
1answer
669 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......
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.
0
votes
1answer
93 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,...
0
votes
0answers
98 views

Join the Fun at Jack’s Casino to get a shot at Jackpot

Jack’s casino dealers are not all prime. But, he gives better odds to get the daily Jackpot by revealing lot more numbers in the sequence in play. That way his Casino is much better than Cryptic ...
7
votes
1answer
346 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
65 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.
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 ...
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 ...
0
votes
0answers
142 views

Ladies and Gentlemen…Please count your cards. Can you beat our prime dealers at our Cryptic Casino to earn some cold cash?

Cryptic Casino employs only prime dealers and encourages the patrons to count the cards unlike other casinos. We introduced a new game recently and encourage you to match your wits with our prime ...
3
votes
1answer
113 views

Find the first three terms of the sequence

Find the missing values in the sequence: $X, X, X, 59, 2, 65, 3, 58, 9, 79, 3, 23$ Hint 1: Hint 2:
1
vote
3answers
123 views

Find the next three terms in the sequence

This sequence consists of triplets; each triplet is linked to each other. $1,36,8,2,48,4,3,60,0,\text{X},\text{X},\text{X}$ The three $\text{X}$'s signify the missing numbers.
5
votes
1answer
125 views

Find the immediate square dancing neighbors, they dance together to perfect square

We live in a community of houses sequentially numbered from 1 to 100. We all love square dancing but only two immediate neighbors are joy to watch. If you concatenate their house numbers, it forms a ...
17
votes
2answers
2k views

We are two immediate neighbors who forged our own powers to form concatenated relationship. Who are we?

Our concatenated number is $ \overline{ABAC}, $ where $ A, B, C $ are all positive digits (1 - 9). Our relationship is $$ \overline{ABAC} = A^A + B^B + A^A + C^C $$ Who are we?
9
votes
1answer
599 views

Narcissistic cube asks who are we?

I am a five digit narcissistic cube who likes to display my root right upfront. I also have hidden it in the back of my four digit cube brother. Who are we?
6
votes
5answers
986 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 ...
-9
votes
1answer
90 views

Number of days in a normal year expressed with five consecutive positive integers [closed]

Given $D$ is the total number of days in a normal year $a$, $b$ are positive integers $P$, $Q$, $R$, $S$, $T$ are consecutive integers Figure them out by combining the following six expressions ...
19
votes
6answers
1k views

My Sixteen Friendly Students

I have sixteen students in my class who sit in four rows of four. Each week they sit in a different order. After a number of weeks every student has sat next to every other student, next meaning ...
12
votes
3answers
2k views

99 coins into the sacks

You have 99 coins that you need to place into any number of sacks. After doing so, you write on each one the number of sacks that are lighter than that sack. For example, if you put 98 coins into one ...
-1
votes
2answers
157 views

Excellent Bike Riders. All under 100. Find the missing members marked x

Excellent Bike Riders. All under 100. Find the missing members marked x. They are all members of special club. 97 X 59 29 X 23 X 7 X