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- \(65 + 20 = \ldots\)
- \(23 + 19 = \ldots\)
- \(20 + 25 = \ldots\)
- \(84 + 3 = \ldots\)
- \(27 + 67 = \ldots\)
- \(21 + 51 = \ldots\)
- \(46 + 42 = \ldots\)
- \(12 + 31 = \ldots\)
- \(36 + 38 = \ldots\)
- \(79 + 16 = \ldots\)
- \(26 + 28 = \ldots\)
- \(32 + 37 = \ldots\)
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Verbetersleutel
- \(\begin{align} & 65 + 20\\= &20+65\\= &20 + \color{green}{60} + \color{red}{5} \\= & \color{green}{80} + \color{red}{5} \\= & \color{red}{85} \end{align}\)
- \(\begin{align} & 23 + 19\\= & \color{green}{20} + \color{red}{3} + \color{green}{10} + \color{red}{9} \\= & \color{green}{30} + \color{red}{12} \\= & \color{green}{30} + \color{orange}{10} + \color{red}{2} \\= & \color{orange}{40} + \color{red}{2} \\= & \color{red}{42} \end{align}\)
- \(\begin{align} & 20 + 25\\= &20 + \color{green}{20} + \color{red}{5} \\= & \color{green}{40} + \color{red}{5} \\= & \color{red}{45} \end{align}\)
- \(\begin{align} & 84 + 3\\= & \color{green}{80} + \color{red}{4} + \color{green}{0} + \color{red}{3} \\= & \color{green}{80} + \color{red}{7} \\= & \color{red}{87} \end{align}\)
- \(\begin{align} & 27 + 67\\= & \color{green}{20} + \color{red}{7} + \color{green}{60} + \color{red}{7} \\= & \color{green}{80} + \color{red}{14} \\= & \color{green}{80} + \color{orange}{10} + \color{red}{4} \\= & \color{orange}{90} + \color{red}{4} \\= & \color{red}{94} \end{align}\)
- \(\begin{align} & 21 + 51\\= & \color{green}{20} + \color{red}{1} + \color{green}{50} + \color{red}{1} \\= & \color{green}{70} + \color{red}{2} \\= & \color{red}{72} \end{align}\)
- \(\begin{align} & 46 + 42\\= & \color{green}{40} + \color{red}{6} + \color{green}{40} + \color{red}{2} \\= & \color{green}{80} + \color{red}{8} \\= & \color{red}{88} \end{align}\)
- \(\begin{align} & 12 + 31\\= & \color{green}{10} + \color{red}{2} + \color{green}{30} + \color{red}{1} \\= & \color{green}{40} + \color{red}{3} \\= & \color{red}{43} \end{align}\)
- \(\begin{align} & 36 + 38\\= & \color{green}{30} + \color{red}{6} + \color{green}{30} + \color{red}{8} \\= & \color{green}{60} + \color{red}{14} \\= & \color{green}{60} + \color{orange}{10} + \color{red}{4} \\= & \color{orange}{70} + \color{red}{4} \\= & \color{red}{74} \end{align}\)
- \(\begin{align} & 79 + 16\\= & \color{green}{70} + \color{red}{9} + \color{green}{10} + \color{red}{6} \\= & \color{green}{80} + \color{red}{15} \\= & \color{green}{80} + \color{orange}{10} + \color{red}{5} \\= & \color{orange}{90} + \color{red}{5} \\= & \color{red}{95} \end{align}\)
- \(\begin{align} & 26 + 28\\= & \color{green}{20} + \color{red}{6} + \color{green}{20} + \color{red}{8} \\= & \color{green}{40} + \color{red}{14} \\= & \color{green}{40} + \color{orange}{10} + \color{red}{4} \\= & \color{orange}{50} + \color{red}{4} \\= & \color{red}{54} \end{align}\)
- \(\begin{align} & 32 + 37\\= & \color{green}{30} + \color{red}{2} + \color{green}{30} + \color{red}{7} \\= & \color{green}{60} + \color{red}{9} \\= & \color{red}{69} \end{align}\)