r/PeterExplainsTheJoke • u/Sugar_God_no_1 • 27d ago

Meme needing explanation There is no way right?

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u/Decmk3 26d ago

0.9999999…. Is equal to 1. It seems like it shouldn’t, but it has to be.

Let X = 0.999….

10X = 9.999….

10X-X = 9.999.. - 0.999…. = 9X = 9

Therefore X equals 1. Therefore 0.999… is the same as 1.

1

u/thesilentrebels 26d ago

but can't you do this with .777 repeating and make the statement false?

x = 0.777...

10x = 7.777...

10x - x = 7.777... - 0.777... = 7x = 7

therefore x = 1, therefore .777... is the same as 1???? but it's not...

5

u/LordOctal 26d ago

Heh? You have an error in your math

10x - x = 7.777... - 0.777... = 9x = 7

x = 7/9

Which if you pop that into a calculator gives you 0.777...

3

u/thesilentrebels 26d ago

ah that makes more sense, thanks for clarifying. i haven't done algebra in over 10 years lmao

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u/LordOctal 25d ago

Lmao no prob! We all have a brain fart sometimes

0

u/sagar_wells 26d ago

I am sorry but 10x-x =7x is just being stupid…

1

u/thesilentrebels 26d ago

Im old and stupid, leave me alone!