$ \text{Gegeben:}\\\text{Seite} \qquad a \qquad [m] \\ \\ \text{Gesucht:} \\\text{Diagonale} \qquad d \qquad [m] \\ \\ d = a\cdot \sqrt{2}\\ \textbf{Gegeben:} \\ a=1\frac{2}{5}m \qquad \\ \\ \textbf{Rechnung:} \\ d = a\cdot \sqrt{2} \\ a=1\frac{2}{5}m\\ d = 1\frac{2}{5}m\cdot \sqrt{2}\\\\d=1,98m \\\\\\ \small \begin{array}{|l|} \hline a=\\ \hline 1\frac{2}{5} m \\ \hline 14 dm \\ \hline 140 cm \\ \hline 1,4\cdot 10^{3} mm \\ \hline 1,4\cdot 10^{6} \mu m \\ \hline \end{array} \small \begin{array}{|l|} \hline d=\\ \hline 1,98 m \\ \hline 19,8 dm \\ \hline 197\frac{98}{99} cm \\ \hline 1,98\cdot 10^{3} mm \\ \hline 1,98\cdot 10^{6} \mu m \\ \hline \end{array}$