Questions tagged [number-property]
Puzzles that use number properties such as even and odd, multiples of numbers, part of a well-known sequence (i.e. Fibonacci) or theorem (Pythagorean relations) or others in part of the method to solve the question.
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After the funeral
The mood was sombre in the lawyer’s office. Eight members of the Picodie family gathered together to hear the reading of their recently deceased father’s will. Around the table sat Eli, Ron, Agnes, ...
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What is a BEN Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it a BEN Number™.
Use the following examples ...
- 5,621
27
votes
1
answer
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What is a Chess Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it a Chess Number™.
Use the following examples ...
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2
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What is a RAP Number™?
Taking inspiration from "What is the word™" series, here the numbers conforms to a special rule, I call it a RAP number™.
Use the following examples below to find the rule.
RAP number™
NOT ...
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What node does 11 point to?
If we included 11 in the diagram below, which node would it connect to?
Hint 1
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What is the secret operator?
There is a secret operator $F$ that takes two whole numbers and outputs a new number. For example
$$\begin{split}F(6,9) &= 15\\
F(66,11) &= 110 \\
F(86,18) &= 179\end{split}$$
Can you ...
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Which two students spoke wrongly? [duplicate]
A teacher wrote a large number on the board and asked the students to tell about the divisors of the number one by one.
The 1st student said, "The number is divisible by 2."
The 2nd student said, "...
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Scrabble with prime numbers!
How to Play
Overall, gameplay is very similar to typical Scrabble; however, unlike typical Scrabble, you'll be using digits instead of letters (we'll cover your tile bag later). The objective is to ...
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What is the Color Code™?
Inspired from Can you name the country code? and What is a Number™? series
$
\begin{gather}
% custom template - reuse if you may
\def\S#1#2{\Space{#1}{21px}{#2px}}\def\P#1{\V{#1em}}\def\V#1{\S{#1}{9}}...
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What number goes in the ?? box?
A simple pattern puzzle
What is the number in the ?? box? Why? No programming please.
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What is a Hope & Love Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it a Hope & Love Number™.
Use the following ...
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2
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Largest number with no repeating digit pairs
What is the largest whole number that you can form, such that no pair of consecutive digits occurs more than once? For example you can have 34543, but you cannot have 34534 as the pair "34" ...
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Hiker's Cabin Mystery | Pt. II
See Part I | See Part III
Nice one, @GarethMcCaughan!
Finally, you've gotten into his computer using the password you managed to decode from his clues... but there's another issue! There is a ...
- 3,111
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Making a 10 digit number divisible by 3
Alice and Bob play the following game, taking turns. Alice starts and writes a single digit from 0 to 9 at the blackboard.
At every turn, each player adds a single digit at the right of the current ...
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What is a Voluminous Number™?
In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles.
If a number conforms to a special rule, I call it a Voluminous Number™.
Use the ...
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Which positive integers have at least one positive integer multiple such that the base 10 representation of that multiple has only even digits?
Which positive integers N have the property that there exists at least one positive integer multiple of N such that the base 10 representation of that multiple has only even digits?
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The largest Saturday number
No weekend love yet shown, therefore I will fix that.
A Saturday number is a number in which for all $1 \le i \le l$, where $l$ is the length of the number, the first $l$ digits (from the left) divide ...
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What is a Heptagon Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it a Heptagon Number™.
Use the following ...
- 5,621
12
votes
1
answer
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What is a Trinity Number™?
This is inspired by the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles, and the Number™ series.
If a number conforms to a special rule, I call it a ...
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What do 84, 96 and 108 have in common?
There's a certain property that's shared between (as far as I know) infinite positive integers including 84, 96 and 108. Below are the first thousand numbers with this property; I added that many in ...
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Dead By Daylight
This puzzle is a reference to a game, Dead By Daylight. Though you don't need a knowledge about the game. Consequently, there is no "video-games" tag.
Story
The Entity wants to have the ...
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1
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Lawbreaking by the numbers
Special Agent Benford has been stymied by a third unsolved case of
miscreant creative accounting and will voluntarily retire
from the Fraudulent Numbers Task Force.
Benford’s ability to detect ...
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Welcome to the Acme Corporation - please find your floor number
Welcome to the Acme Corporation.
The Acme Corporation is the greatest company in the world, and it should be your utmost honor and privilege to be employed as an associate of the Corporation.
The ...
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What is an IJKLMN Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it an IJKLMN Number™.
Use the following examples ...
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10
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1
answer
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I'm thinking of a number
The unusual thing about this number is that the most common phrases that use it are wrong. That is, while someone may often say there are X As in a B, the actual number is not X.
What number am I ...
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I'm a number with a special product, so name me when you think you've got it
In the blocks that come before,
their special product tells us more.
To guess my scheme you'll need calculation,
but only little tests of recreation.
Each block contains atoms strong as Thor,
...
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2
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Ten-digit number that satisfy divisibilty rules for 2,3,4,5,6,7,8,9,10&11
Question:
Arrange the digits 1,2,3,4,5,6,7,8,9,0 to make a ten-digit Number that satisfies all of the divisibility rules for 2,3,4,5,6,8,9,10,&11. BONUS: make the number also divisible by 7
- 101
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What mysterious whole number am I?
From my second point of view I copy that amount of first.
I am the dominant side of two but for many I'm the worst.
I'll be tricky to find but today might be your day,
after all my neighbour is 2/3 of ...
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Consecutive integers with digit sum divisible by 19
What is the smallest positive integer N, such that the digit sum of N and N+1 are both divisible by 19?
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Know your primes
Did you know that a prime, regardless of its base, is always a prime?
I am looking for a prime. It’s the largest of its kind.
In solving this puzzle, the answer you may find.
...
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1
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What's the significance of this pattern?
Note, this is my first submission, let me know if I broke the rules.
What is the significance of the following sequence of # signs?
...
9
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2
answers
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What is an Encoding Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it an Encoding Number™.
Use the following ...
- 5,621
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7
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How can four be the half of five? [closed]
I came across this enigmatic one-liner:
How can four be half of five?
Can you figure it out?
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When should this question be answered?
If you hover your mouse over the time marked in the right-bottom corner of this post, then you will see a string showing the exact time that I post this question, which reads ...
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Which famous mathematical constant can be celebrated on these dates?
Which famous mathematical constant can be celebrated on these dates?
April 11, 2020
April 12, 2021
April 12, 2022
April 12, 2023
April 11, 2024
April 12, 2025
April 12, 2026
April 12, 2027
April 11, ...
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What comes next in this sequence, and why?
I'm having the hardest time with this sequence puzzle. The mobile game I play (which asked me the question) doesn't provide answers or explanations for incorrect answers, and I'm searching online so I ...
- 321
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2
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Half and Double Value
A 3 year old child tried to input or copy a number (written on the paper) to a calculator but he messed up with the digit places. All the digits are there but the value of the number he inputed ...
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A "Find the Path" Puzzle
I invented a puzzle, inspired by Simon Tatham's Portable Puzzle Collection. Is there anything that it could improve on? Was it too easy, or was it too hard? Anything I could add? What must I call it?
...
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Discover the six-character password!
You are given several pieces of paper which are as follows:
(Unfortunately, a textual rendering is very difficult with this puzzle, so if someone can offer a suggestion on how to do it, that would be ...
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Multilanguage generalization of "What number is that? Asks Grandpa"
This is a multilingual generalized follow-on to "What number is that? Asks Grandpa", which I restate as:
"What is the smallest positive English integer N, for which if you take its WORD anagram and ...
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What is a Finale Number™?
This is in the spirit of the What is a Word/Phrase™ series started by JLee with Number version puzzles.
If a number conforms to a special rule, I call it a Finale Number™.
Use the following examples ...
- 5,621
7
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2
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When do decimal-coded binary numbers XOR to zero?
Background definition: XOR on numbers
Given two non-negative integers $x$ and $y$, let $x\oplus y$ denote the bitwise exclusive or (XOR) of the numbers $x$ and $y$. This is the result of writing $x$ ...
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Integers containing all ten digits
It is known that most positive integers contain at least one copy of each of the ten digits.
What is the largest n such that at most 50% of the integers in the set [1,2,3,...,n]
contain at least one ...
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1
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I'm a Proper Divisor
Ann and Bob are playing a number game. Ann starts with the number 60. Then she subtracts a proper divisor of 60 from it. Bob then takes the number Ann made and subtracts one of its proper divisors ...
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What is larger than largest, your intuitions are tarnished. (What am I?)
You might call me a number,
but that would be a blunder.
In class you may have been told otherwise,
but I tell you now that those were all lies.
I'm in the deck of the cards,
as big as them come.
...
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2
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What is the name of AB×B×A=BBB puzzles?
Some puzzles goes as follows: Solve AB×B×A=BBB, where different letters denote different numbers and A and B are not zero.
What is the name for these types of puzzles?
Edit. I fixed my mistake in ...
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Who's that Simple Pokémon™?
For every alphabet (A to Z), there exists at most one corresponding Simple Pokémon™. As of Generation 8, it goes:
...
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Mathematical Coincidence
A friend came up to me today with a deck of cards, and put these 6 into a group:
2 3 5 7 J K
The other 7 values went into another group:
A 4 6 8 9 10 Q
He then challenged me to find the reason ...
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1
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What do numbers have?
Numbers 0 through 9 each have a number of something.
0 has 6.
1 has 2.
2 has 5.
3 has 5.
4 has 4.
How many do 5, 6, 7, 8 and 9 have?
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Find the location of the royal artifacts
London, 13:20
While media and experts are still baffled on how Inspector Arbor caught Norman Erdmann (can you solve it? See here) Arbor himself has no time to rest.
Police has already questioned ...
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