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Easily compute a wide variety of mathematical equations with this Casio FX-300MS Plus Scientific Calculator. Casio FX300MSPLUS 10-digit, 2-line scientific calculator features a large display that shows the problem as you write it, and then shows the answer alongside it for easy reference. If you make an error, you can quickly clear it with the backspace key. Calculator offers one independent memory key and six constant memory keys.

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Casio FX-81, 1980 Ad. : r/vintageads