Brug Mix (reeks 2)

Reken uit

\(40 + 13 = \ldots\)

\(\begin{align} & 40 + 13\\= &40 + \color{green}{10} + \color{red}{3} \\= & \color{green}{50} + \color{red}{3} \\= & \color{red}{53} \end{align}\)