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52 votes
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After the funeral

So first is to note that I’d imagine that Julia got nothing because As it turns out, To Agnes, I bequeath 12,000 pounds. To Eli, I bequeath 201,000 pounds. To Eric, I bequeath 95,000 pounds. To ...
El-Guest's user avatar
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39 votes

How to solve 1 2 3 4 5 = 5 4 3 2 1 (insert five pluses to make it equal)? A thorough solution needed

Well, here is how I would (and did) solve it: First step: Without the « five + » constraint Second step: Getting rid of some « + » A solution we found: Extra note: finding all solutions
Jujustum's user avatar
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30 votes
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What is a Chess Number™?

A Chess Number™ is a number that Here are the results for chess numbers: And for not chess numbers:
Lukas Rotter's user avatar
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28 votes
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How to solve 1 2 3 4 5 = 5 4 3 2 1 (insert five pluses to make it equal)? A thorough solution needed

Another way to think about it is to start with plus signs in all eight positions. The sums are equal at $15$. When you remove a plus sign you add
Ross Millikan's user avatar
26 votes
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Largest number with no repeating digit pairs

I believe this is the largest number that meets that criteria: Reasoning:
Joe Kerr's user avatar
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25 votes
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What node does 11 point to?

RobPratt's user avatar
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24 votes
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How can four be the half of five?

One answer that springs to mind
hexomino's user avatar
  • 136k
21 votes

Ten-digit number that satisfy divisibilty rules for 2,3,4,5,6,7,8,9,10&11

This is a good problem to attack by computer: So I thought, how far can we go? Code used (Python 3 IDLE):
boboquack's user avatar
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21 votes

How can four be the half of five?

If you make a pentagon, / \ |_| and you cut it in half from top to bottom you get: /| |\ |_| |_| that is, you get two ...
a20's user avatar
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19 votes
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Which two students spoke wrongly?

Okay so the first step is to realize that: Also, Hence, Also, we see that Eliminating all of those, we get that the answer is
NL628's user avatar
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17 votes
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What is a RAP Number™?

Does RAP stand for Some examples:
Sconibulus's user avatar
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17 votes

What is a RAP Number™?

Possibly a RAP number may be one where the numbers are
Tom's user avatar
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17 votes
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I'm thinking of a number

A number which fits is Hint 1: Hint 2:
Tom's user avatar
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17 votes
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What is a BEN Number™?

Ok, so a Ben number is a number that Proof: The hints helped so: 1- 2- 3- 4- 5- 6- 7- What helped me The largest BEN number is then
Pretzel's user avatar
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17 votes

Make numbers 1 - 30 using the digits 2, 0, 2, 4

Complete solution that doesn't use concatenation.
Albert.Lang's user avatar
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16 votes
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The largest Saturday number

The more common name for a Saturday number is There is a good argument for believing that they cannot grow to any length: The longest Saturday number is: To be honest, I wrote a computer program to ...
Jaap Scherphuis's user avatar
16 votes

Making a 2n-digit number divisible by 9

I believe that Bob can win if (and only if) n is
SQLnoob's user avatar
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15 votes
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When should this question be answered?

I'm a very impatient person so I've decided not to wait around to post an answer at the right time which I think will be Reasoning
hexomino's user avatar
  • 136k
15 votes

Largest number with no repeating digit pairs

What is the correct answer depends on the number system that is used. In Hexadecimal, a common thing to display data from computers, the highest number is (with a space separating each block) In ...
Trish's user avatar
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14 votes
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What is a Heptagon Number™?

A Heptagon number is For each listed number: The numbers in the other column do not have this property.
Matt's user avatar
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14 votes

What comes next in this sequence, and why?

OH MY GOD I just got it. Like, as I was looking at my own question. Boy do I feel silly. The next number is PHEW that was bugging the bejeezus out of me! Hahaha
Dana's user avatar
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14 votes
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Which famous mathematical constant can be celebrated on these dates?

The constant is Because the dates are
Daniel Mathias's user avatar
14 votes
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Consecutive integers with digit sum divisible by 19

I think it is Reasoning:
Glorfindel's user avatar
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13 votes
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Multilanguage generalization of "What number is that? Asks Grandpa"

In Mandarin Chinese: 十二 and 二十 Am I cheating? In Braille: In Arabic: In Sino-Korean Cardinal Numerals written in Hangul: In Morse Code: In Roman Numerals: For Binaries if... Note for Latin: ...
JKHA's user avatar
  • 6,033
13 votes

When should this question be answered?

Having 5 divisors means A standard number-theoretical way to observe this is So what we need to do now is Here is the code in Factor: The output is
Bubbler's user avatar
  • 15.1k
13 votes

Scrabble with prime numbers!

This is a huge question, and I think people can help each other here so I'm going to start with some initial strategy: I have set up this board: Which allows for this move: For a score of 2372 (...
TwoBitOperation's user avatar
13 votes

How can four be the half of five?

Another (kind of linguistic) answer:
trolley813's user avatar
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13 votes

Which positive integers have at least one positive integer multiple such that the base 10 representation of that multiple has only even digits?

I think that the positive integers with this property are Proof
hexomino's user avatar
  • 136k
13 votes

How to solve 1 2 3 4 5 = 5 4 3 2 1 (insert five pluses to make it equal)? A thorough solution needed

The plus sign is also a unary operator. Therefore a solution with four plus signs is also valid for five plus signs:
tolos's user avatar
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