What is the sum of X+XX+XXX+XXXX?
12.06.2025 00:05

11010X
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
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)
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
New map shows Bay Area locations with highest risk of ember-driven wildfires - East Bay Times
However, X +X^2 +X^3 + X^4 is a valid algebraic answer,
1234X
It’s a matter of interpretation.