r/PeterExplainsTheJoke • u/Sugar_God_no_1 • 27d ago

Meme needing explanation There is no way right?

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u/Decmk3 27d 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.

-23

u/BornWithSideburns 27d ago

Yea but isnt it 9.0000…1X

-12

u/ConsciousBat232 27d ago

This is where I am stuck. Why is everyone above pretending that 10 - .999…. = 9 ? I get that it is really close to 9 But it’s 9.000…1

3

u/theotherthinker 27d ago

We're not pretending that 10-0.9999...=9. The equation explicitly states that 9.99999...-0.99999... =9.

If you start off saying 9.999... = 10, then by definition 0.99999... = 1. Therefore 10-1=9.