Paul Marks on X: "@zsk @jimeasterbrook Casio fx-29 calculator ... still working and eating all my pi since 1977. Fitted well in the knee pockets of high waisters - anyone remember those?
My high school calculator Casio fx - 39 from 1981 year and his friend ElsiMate : r/calculators
Vintage Retro 1970s Casio Scientific Calculator Fx-39 Made in Japan | Acquisti Online su eBay
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