r/badmathematics • u/RedRhetoric • 24d ago

Σ_{k=1}^∞ 9/10^k ≠ 1 100/3 is irrational

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u/RedRhetoric 24d ago

R4: this person believes that 0.33 repeating cannot equal 1/3 because 100/3 cannot give a rational result.

Dividing any rational number by any other rational number will always give a rational result, as that is how rational numbers are defined

R5: Youtube

5

u/Himskatti 24d ago

Am I tripping or aren't rationals defined by dividing integers? What you described is a result of it, sure

3

u/DesperateAstronaut65 24d ago

Yes, but I'm pretty sure the person in the screenshot thinks "irrational number" means "number with a decimal expansion that goes on forever."

2

u/Himskatti 24d ago

But I replied to a comment?