Brug Mix (reeks 2)

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\(46 + 21 = \ldots\)

\(\begin{align} & 46 + 21\\= & \color{green}{40} + \color{red}{6} + \color{green}{20} + \color{red}{1} \\= & \color{green}{60} + \color{red}{7} \\= & \color{red}{67} \end{align}\)