Answer
$1$ to $491$
Work Step by Step
There are $500$ total parts, and $10$ do not work, so there are $490$ that do work. There are two extreme cases:
1) If the first part selected is a nonconforming part, then the random variable is $1$.
2) If every single conforming part is selected before the nonconforming parts, then the random variable is $490+1=491$.
Thus the range is $1$ to $491$