I actually used an abacus during a math test in high school because we weren't allowed to use programmable calculators, and all I had access to was my Dad's fancy TI something or other. The beads made so much noise that my teacher said next time she would trust me to use my dad's calculator.

These days I use a Casio - it has the ability to convert Hexadecimal (base 16) to decimal easily.

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1984 300TD