What is the sum of X+XX+XXX+XXXX?
13.06.2025 00:39

and for binary would be
However, X +X^2 +X^3 + X^4 is a valid algebraic answer,
It’s a matter of interpretation.
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
What is the sum of X+XX+XXX+XXXX?
1234X
Trump's sons distance themselves from new Trump-branded crypto venture - ABC News
11010X
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)
*Note that the abbreviation XL (for XXXX) appeared quite late in the Roman period, and never found universal favour
No Social Security Payments for 12 Days: June 2025 Schedule Explained - Fingerlakes1.com