What is the sum of X+XX+XXX+XXXX?
12.06.2025 06:54

It’s a matter of interpretation.
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)
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1234X
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
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11010X
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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