# 300 followers problem!

Let $$A = \underbrace{\overline{123456789}}_{\text{set: 1}}$$ and $$B = \underbrace{\overline{987654321}}_{\text{set: 2}}$$

Let, $x = \underbrace{\overline{123456789987654321\dots 123456789987654321}}_{\text{300 alternate sets or 150}\overline{AB} \text{'s}}$

Find the sum of digits of $$9x$$.

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