My Strange Observation: Anything Multiplied by 9 Equals 9

AI Thread Summary
Multiplying any number by 9 results in a sum of digits that equals 9, which is an interesting numerical property. This phenomenon does not apply to other numbers, making it unique. The discussion suggests exploring this behavior through physics to develop a theory. Additionally, similar patterns are noted in different numeral systems, such as 1 in binary and 2 in ternary. This observation highlights a property related to the largest integer in these systems.
decibel
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i was playing with numbers the other day and noticed this

- Anything multiplied by 9, will equal 9 when added

this is really weird considering that it doesent work with any #

i know this belongs in the math forums, but using physics could generate a good theory,

it may be stupid but u never know...so any thoughts?, any observations would be appreciated also
 
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You will find the same "strangness" attached to 1 in a binary system, 2 in a teriary system. This behavior is a property of the largest integer.

Yes this belongs in the Math forums.
 

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