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

Last Updated: 22.06.2025 00:23

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

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

1234X

11010X

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

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

It’s a matter of interpretation.

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and for binary would be

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)

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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