Brug Mix (reeks 1)

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\(11 + 57 = \ldots\)

\(\begin{align} & 11 + 57\\= & \color{green}{10} + \color{red}{1} + \color{green}{50} + \color{red}{7} \\= & \color{green}{60} + \color{red}{8} \\= & \color{red}{68} \end{align}\)