133- What is the average of the largest and smallest three-digit numbers of the form $\overline{aba}$ that are multiples of 12? (1) $348$ (2) $450$ (3) $570$ (4) $574$
\textbf{133-} What is the average of the largest and smallest three-digit numbers of the form $\overline{aba}$ that are multiples of 12?
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(1) $348$ \hfill (2) $450$ \hfill (3) $570$ \hfill (4) $574$
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