so we are trying to maximize $\dfrac{382 + x}{2} - \dfrac{382 + y}{2}$, assuming $x$ is the greater number. if the set is inclusive, we have $150 \leq y \leq x \leq 350$
to maximize the difference, $x = 350$ and $y = 150.$ the fractions of each are $\dfrac{732}{2}$ and $\dfrac{532}{2}$, so the difference is $\dfrac{732-532}{2} = \dfrac{200}{2} = \boxed{100.}$
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