Questions tagged [mathematics]
A puzzle related to mathematical facts and objects, whose solution needs mathematical arguments. General mathematics questions are off-topic but can be asked on Mathematics Stack Exchange.
4,707
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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
2
answers
108
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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, ...
1
vote
1
answer
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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
1
answer
154
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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
2
answers
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SAD!!!...System Access Denied..you got three minutes to input three digit passcode
Hexagon is a 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.
Today ...
1
vote
3
answers
471
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 ...
5
votes
3
answers
257
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
2
answers
251
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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 explode
before you know it.
What am I?
0
votes
2
answers
115
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
1
answer
298
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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
2
answers
114
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
2
answers
156
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 ...
15
votes
6
answers
2k
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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 ...
4
votes
2
answers
169
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
1
answer
110
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
1
answer
205
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
2
answers
192
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
1
answer
121
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
3
answers
682
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
1
answer
91
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
2
answers
160
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
2
answers
182
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
1
answer
706
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
3
answers
2k
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
1
answer
144
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(?)
$(255,153,51x)(153,0xx,51x) = 669900$
$(255,204,51x)(204,51x,51x) = 339900$
$(153,153,204)(0xx,204,...
4
votes
1
answer
244
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
1
answer
412
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
1
answer
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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
3
answers
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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
5
answers
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 ...
3
votes
1
answer
137
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
3
answers
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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.
6
votes
1
answer
158
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
2
answers
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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
1
answer
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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
5
answers
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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
1
answer
136
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 ...
18
votes
6
answers
2k
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 ...
14
votes
3
answers
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
2
answers
168
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
1
answer
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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
3
answers
504
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
1
answer
222
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
1
answer
146
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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
2
answers
719
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
1
answer
245
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 $(1,72)$ ...
5
votes
2
answers
239
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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 ...
2
votes
1
answer
120
views
The NANNP Grid ( Not another Next Number Puzzle )
Simply figure out the last row...
11
votes
7
answers
2k
views
Missing Piece of Pie - Can you find it?
A piece is missing!
What should it be?
0
votes
1
answer
92
views
Place Your Bets 3 , last of the series
A harder sequence to figure out...
What are the next 4 cards, including suits?