Brug Mix (reeks 1)

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\(15 + 64 = \ldots\)

\(\begin{align} & 15 + 64\\= & \color{green}{10} + \color{red}{5} + \color{green}{60} + \color{red}{4} \\= & \color{green}{70} + \color{red}{9} \\= & \color{red}{79} \end{align}\)