What is the sum of X+XX+XXX+XXXX?

Last Updated: 03.07.2025 00:01

What is the sum of X+XX+XXX+XXXX?

1234X

*Note that the abbreviation XL (for XXXX) appeared quite late in the Roman period, and never found universal favour

11010X

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It’s a matter of interpretation.

and for binary would be

as would be assuming that these are representations of conventional numbers, in which case the answer for number bases of five or more would be

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However, X +X^2 +X^3 + X^4 is a valid algebraic answer,

Given the use of upper case, I personally would initially assume Roman numerals*, so the answer would be C (100 in present-day decimal notation)

What is the sum of X+XX+XXX+XXXX?

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