1957 AMC 12 Question 38
AMC12 · 1957 AMC 12
From a two-digit number $N$ we subtract the number with the digits reversed and find that the result is a positive perfect cube. Then:
$N$ cannot end in $5$
$N$ can end in any digit other than $5$
$N$ does not exist
there are exactly $7$ values for $N$
there are exactly $10$ values for $N$