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- \(50 + 15 = \ldots\)
- \(13 + 70 = \ldots\)
- \(30 + 22 = \ldots\)
- \(18 + 80 = \ldots\)
- \(54 + 10 = \ldots\)
- \(31 + 40 = \ldots\)
- \(80 + 13 = \ldots\)
- \(19 + 10 = \ldots\)
- \(55 + 30 = \ldots\)
- \(21 + 50 = \ldots\)
- \(20 + 36 = \ldots\)
- \(12 + 10 = \ldots\)
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Verbetersleutel
- \(\begin{align} & 50 + 15 \\= & 50 + \color{green}{10} + \color{red}{5} \\
= & \color{green}{60} + \color{red}{5} \\
= & \color{red}{65} \end{align}\)
- \(\begin{align} & 13 + 70 \\
= & 70 + 13 \\= & 70 + \color{green}{10} + \color{red}{3} \\
= & \color{green}{80} + \color{red}{3} \\
= & \color{red}{83} \end{align}\)
- \(\begin{align} & 30 + 22 \\= & 30 + \color{green}{20} + \color{red}{2} \\
= & \color{green}{50} + \color{red}{2} \\
= & \color{red}{52} \end{align}\)
- \(\begin{align} & 18 + 80 \\
= & 80 + 18 \\= & 80 + \color{green}{10} + \color{red}{8} \\
= & \color{green}{90} + \color{red}{8} \\
= & \color{red}{98} \end{align}\)
- \(\begin{align} & 54 + 10 \\
= & 10 + 54 \\= & 10 + \color{green}{50} + \color{red}{4} \\
= & \color{green}{60} + \color{red}{4} \\
= & \color{red}{64} \end{align}\)
- \(\begin{align} & 31 + 40 \\
= & 40 + 31 \\= & 40 + \color{green}{30} + \color{red}{1} \\
= & \color{green}{70} + \color{red}{1} \\
= & \color{red}{71} \end{align}\)
- \(\begin{align} & 80 + 13 \\= & 80 + \color{green}{10} + \color{red}{3} \\
= & \color{green}{90} + \color{red}{3} \\
= & \color{red}{93} \end{align}\)
- \(\begin{align} & 19 + 10 \\
= & 10 + 19 \\= & 10 + \color{green}{10} + \color{red}{9} \\
= & \color{green}{20} + \color{red}{9} \\
= & \color{red}{29} \end{align}\)
- \(\begin{align} & 55 + 30 \\
= & 30 + 55 \\= & 30 + \color{green}{50} + \color{red}{5} \\
= & \color{green}{80} + \color{red}{5} \\
= & \color{red}{85} \end{align}\)
- \(\begin{align} & 21 + 50 \\
= & 50 + 21 \\= & 50 + \color{green}{20} + \color{red}{1} \\
= & \color{green}{70} + \color{red}{1} \\
= & \color{red}{71} \end{align}\)
- \(\begin{align} & 20 + 36 \\= & 20 + \color{green}{30} + \color{red}{6} \\
= & \color{green}{50} + \color{red}{6} \\
= & \color{red}{56} \end{align}\)
- \(\begin{align} & 12 + 10 \\
= & 10 + 12 \\= & 10 + \color{green}{10} + \color{red}{2} \\
= & \color{green}{20} + \color{red}{2} \\
= & \color{red}{22} \end{align}\)