What is the sum of X+XX+XXX+XXXX?
Last Updated: 22.06.2025 03:20

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
and for binary would be
Apple Knows AI Isn’t What People Really Want, but It Can’t Say That - Gizmodo
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
1234X
However, X +X^2 +X^3 + X^4 is a valid algebraic answer,
SpaceX launch from California sends 26 Starlink satellites into low Earth orbit - Space
It’s a matter of interpretation.
What is the sum of X+XX+XXX+XXXX?
11010X
James Hagens’ Islanders homecoming is no longer just a pipe dream - New York Post