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- \(42 + 25 = \ldots\)
- \(66 + 29 = \ldots\)
- \(42 + 19 = \ldots\)
- \(22 + 51 = \ldots\)
- \(57 + 26 = \ldots\)
- \(34 + 13 = \ldots\)
- \(19 + 21 = \ldots\)
- \(61 + 17 = \ldots\)
- \(38 + 22 = \ldots\)
- \(51 + 38 = \ldots\)
- \(85 + 1 = \ldots\)
- \(56 + 23 = \ldots\)
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Verbetersleutel
- \(\begin{align} & 42 + 25\\= & \color{green}{40} + \color{red}{2} + \color{green}{20} + \color{red}{5} \\= & \color{green}{60} + \color{red}{7} \\= & \color{red}{67} \end{align}\)
- \(\begin{align} & 66 + 29\\= & \color{green}{60} + \color{red}{6} + \color{green}{20} + \color{red}{9} \\= & \color{green}{80} + \color{red}{15} \\= & \color{green}{80} + \color{orange}{10} + \color{red}{5} \\= & \color{orange}{90} + \color{red}{5} \\= & \color{red}{95} \end{align}\)
- \(\begin{align} & 42 + 19\\= & \color{green}{40} + \color{red}{2} + \color{green}{10} + \color{red}{9} \\= & \color{green}{50} + \color{red}{11} \\= & \color{green}{50} + \color{orange}{10} + \color{red}{1} \\= & \color{orange}{60} + \color{red}{1} \\= & \color{red}{61} \end{align}\)
- \(\begin{align} & 22 + 51\\= & \color{green}{20} + \color{red}{2} + \color{green}{50} + \color{red}{1} \\= & \color{green}{70} + \color{red}{3} \\= & \color{red}{73} \end{align}\)
- \(\begin{align} & 57 + 26\\= & \color{green}{50} + \color{red}{7} + \color{green}{20} + \color{red}{6} \\= & \color{green}{70} + \color{red}{13} \\= & \color{green}{70} + \color{orange}{10} + \color{red}{3} \\= & \color{orange}{80} + \color{red}{3} \\= & \color{red}{83} \end{align}\)
- \(\begin{align} & 34 + 13\\= & \color{green}{30} + \color{red}{4} + \color{green}{10} + \color{red}{3} \\= & \color{green}{40} + \color{red}{7} \\= & \color{red}{47} \end{align}\)
- \(\begin{align} & 19 + 21\\= & \color{green}{10} + \color{red}{9} + \color{green}{20} + \color{red}{1} \\= & \color{green}{30} + \color{red}{10} \\= & \color{red}{40} \end{align}\)
- \(\begin{align} & 61 + 17\\= & \color{green}{60} + \color{red}{1} + \color{green}{10} + \color{red}{7} \\= & \color{green}{70} + \color{red}{8} \\= & \color{red}{78} \end{align}\)
- \(\begin{align} & 38 + 22\\= & \color{green}{30} + \color{red}{8} + \color{green}{20} + \color{red}{2} \\= & \color{green}{50} + \color{red}{10} \\= & \color{red}{60} \end{align}\)
- \(\begin{align} & 51 + 38\\= & \color{green}{50} + \color{red}{1} + \color{green}{30} + \color{red}{8} \\= & \color{green}{80} + \color{red}{9} \\= & \color{red}{89} \end{align}\)
- \(\begin{align} & 85 + 1\\= & \color{green}{80} + \color{red}{5} + \color{green}{0} + \color{red}{1} \\= & \color{green}{80} + \color{red}{6} \\= & \color{red}{86} \end{align}\)
- \(\begin{align} & 56 + 23\\= & \color{green}{50} + \color{red}{6} + \color{green}{20} + \color{red}{3} \\= & \color{green}{70} + \color{red}{9} \\= & \color{red}{79} \end{align}\)