Phone Number riddle: Solve & Remember

  • Context: High School 
  • Thread starter Thread starter tribdog
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Discussion Overview

The discussion revolves around a riddle involving a phone number, where participants attempt to decipher the components of the number based on provided clues. The scope includes mathematical reasoning and problem-solving related to the structure of the phone number, including area code, prefix, and extension.

Discussion Character

  • Exploratory, Mathematical reasoning, Debate/contested

Main Points Raised

  • One participant presents a riddle that describes the phone number's area code, prefix, and extension using specific mathematical conditions.
  • Another participant expresses difficulty in finding digits that satisfy the conditions for the area code, particularly regarding the definition of single-digit numbers and the inclusion of zero.
  • A participant claims to have found a solution for the phone number, providing a specific area code and prefix, but another participant challenges the validity of the extension provided.
  • There is a discussion about the calculations related to the extension, with one participant detailing their reasoning and checking the conditions against the clues given.
  • Another participant offers a different extension, suggesting an alternative solution.

Areas of Agreement / Disagreement

Participants do not reach consensus on the validity of the proposed phone number solutions, particularly regarding the extension. Multiple competing views and solutions are presented, indicating ongoing disagreement.

Contextual Notes

Participants express uncertainty about the definitions of single-digit numbers and the implications of using zero in the context of the riddle. There are unresolved calculations and interpretations related to the clues provided.

Who May Find This Useful

Individuals interested in mathematical puzzles, riddles, and problem-solving techniques may find this discussion engaging.

tribdog
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It's not a toll free call, but if you dial it I'll answer. Here's an easy way to remember my phone number, you just break it into pieces:

the three digit area code:
the first digit is half the second digit and while the product of all 3 is a single digit their sum has two.

the prefix:
three digits, exactly two of which are the same. The difference between the first and the single digit sum of the other two is twice as big as the first is smaller than the single digit product of the other two.

the suffix:
the first two digits and the last two digits (in order) of a ten digit string of single digit numbers popular with both NASA and bomb exploders.

See how easy that was? OH I almost forgot there is also a three digit extension and the first digit equals the second but not the third and the sum of the digits of the product of the sum and the product of the digits of the extension is equal to the sum of the digits of the extension itself.
 
Last edited:
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Oh that is cruel. I was going over how in the hell I could find three digits that multiplied to a single digit but also had one digit twice as large as the other for a good 10 minutes before I remembered 0.

Wait, is 0 considered a single digit number? Is it a single digit number? How is single digit defined? "6" is single digit so "06" is single digit, even though we used two digits. Wait, did I go off on a tangent? :rolleyes:
 
Alkatran said:
Oh that is cruel. I was going over how in the hell I could find three digits that multiplied to a single digit but also had one digit twice as large as the other for a good 10 minutes before I remembered 0.

Wait, is 0 considered a single digit number? Is it a single digit number? How is single digit defined? "6" is single digit so "06" is single digit, even though we used two digits. Wait, did I go off on a tangent? :rolleyes:

I already have the area code, but I have mutliple solutions for the prefix that work, so I gave up.
 
Don't know about the NASA stuff, but here's one solution for the rest:

(480) 833-abcd, ext:114
 
and that ext # doesn't work. try again
 
tribdog said:
OH I almost forgot there is also a three digit extension and the first digit equals the second but not the third and the sum of the digits of the product of the sum and the product of the digits of the extension is equal to the sum of the digits of the extension itself.
Sum of digits of ext itself = 1+1+4=6

Sum=6, product=4 =>product of (sum and product)=6*4=24 => sum of digits of (product of (sum and product))=2+4=6

I don't see the error. Or are you saying there isn't an error, but that's not the number to your phone?
 
my extension is 117
 

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