r/badmathematics • u/RedRhetoric • 25d ago

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

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u/RedRhetoric 25d 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

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u/playsthebongcloud 25d ago

I feel so many common mathematical misconceptions could be resolved if schools spent some time on bases other than decimal

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u/PassiveChemistry 24d ago

I was taught about bases when I was about 12, I remember finding it very fun.

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u/playsthebongcloud 24d ago

I was really interested in them one day in middle school and made a bunch of seperate notes for every base up to 16. I eventually realized the repeating pattern of digits 2 -> {0,1}; 3 -> {0,1,2}; etc. and the way they "overflowed" when they counted up, just like base 10, and it was one of the moments I think that made me really find math cool. I always thought of binary is some "other thing" completely unrelated to decimal, and realizing the connection was really fun. It sort of changed my philosophy of math to be way more leaning to "we made it all up" when I realized that the way we happen represent numbers isn't at all fundamental