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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.

1
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1answer
21 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?
4
votes
2answers
139 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
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3answers
364 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 ...
3
votes
3answers
176 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
161 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
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2answers
58 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 ...
6
votes
1answer
260 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&=\,?\...
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2answers
103 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
108 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
222 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 ...
0
votes
0answers
55 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
140 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
91 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
140 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
177 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
77 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
595 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
82 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
125 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?
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vote
2answers
90 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
662 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
87 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,...
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votes
0answers
88 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 ...
6
votes
1answer
335 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: $$ \overline{CCC} = \overline{UVUVUV} \div \left ( \overline{UV} \times \overline{UV} \right) $$
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1answer
62 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
138 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
111 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:
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vote
3answers
115 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
119 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
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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
598 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?
8
votes
4answers
922 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
88 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
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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 ...
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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
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votes
1answer
186 views

Can you find this abundant dad and his six prime sons?

We are six little prime brothers. All our ages add up to the age of our abundant and old dad who is obviously not in his prime. However, if you pair him up with either of the prime neighbors, they ...
1
vote
3answers
456 views

Solve for the Number in the number..square..cube relationship

Each letter stands for a distinct digit...no computer or calculator needed. Just pure logic and some mental multiplication. CUBE is a concatenated number and it is a cube. X denotes multiplication. (...
5
votes
1answer
118 views

Surviving the Zombie Apocalypse

It is the zombie apocalypse. Your car has limited fuel in it, and you will not be able to refill your tank once you run out. You are planning one final mission to gather supplies. You have identified ...
0
votes
1answer
113 views

He said yes..she said no..they went back and forth..they agreed to [closed]

To call it a Prime. S, N, O are 3 distinct digits that are to be determined by you so that their conclusion is right Full concatenated number: SNOSNOS
5
votes
2answers
636 views

Madam I m Adam..please don’t get mad..you will no longer be prime

Take away $ \overline{MAD} $ from $ \overline{MADMADAM} $ to make her prime. $ \overline{ADAM} $ is prime too if he does not get mad: $ \overline{MADADAM}. $ $ M, A, D $ are 3 distinct digits that ...
6
votes
1answer
198 views

XOR: Is it possible to get $a$ and $b$ if I have $a \oplus b$ and $a \times b$?

Intuitively I would say yes but I can't find a way to prove it. I tried with small values and bruteforcing shows that there seems to only be one solution given a distinct tuplet. For example $(1,72)$ ...
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2answers
189 views

SafeCracker #2 - The Mission Continues

Thanks to an alert StackE user, we were able to get the first safe open. Mission Details This next safe is in a former employee's house. He is gone for now, so we have no time to spare. We weren't ...
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1answer
82 views
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1answer
85 views

The Walking StackMan [closed]

Simply figure out how long I had to walk... Ps. Stop googling to find similar answers! I want to see you challenge yourself, especially our younger crowd. :)
10
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7answers
2k views

Missing Piece of Pie - Can you find it?

A piece is missing! What should it be?
0
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1answer
69 views

Place Your Bets 3 , last of the series

A harder sequence to figure out... What are the next 4 cards, including suits?