1971 AHSME Problems/Problem 11
The numeral in base a represents the same number as in base . Assuming that both bases are positive integers, the least possible value of written as a Roman numeral, is
. . The smallest possible value of is . Then, . However, the digit is not valid in base , so we have to try a larger value. , gives a value of , for , which is valid.
, which is as a roman numeral, and thus the answer is