What is the sum of X+XX+XXX+XXXX?
14.06.2025 00:50
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
11010X
It’s a matter of interpretation.
*Note that the abbreviation XL (for XXXX) appeared quite late in the Roman period, and never found universal favour
1234X
and for binary would be
What is the sum of X+XX+XXX+XXXX?
However, X +X^2 +X^3 + X^4 is a valid algebraic answer,