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\(4 + 69 = \ldots\)

\(\begin{align} & 4 + 69 \\= & 69 + 4 \\= & 69 + \color{green}{1} + \color{red}{3} \\= & \color{green}{70} + \color{red}{3} \\= & \color{red}{73} \end{align}\)