Giải bài 1 trang 73 - SGK Toán lớp 3

a)

$\left. \begin{align} & \begin{matrix} 350 \\ 35\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,\,\,00\, \\ & \,\,\,\,\,\,0\, \\ & \,\,\, \overline{\,\,\,0\,} \\ \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{7}{50} \\ \begin{matrix} {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$                         $\left. \begin{align} & \begin{matrix} 420 \\ 42\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,\,\,00\, \\ & \,\,\,\,\,\,0\, \\ & \,\,\, \overline{\,\,\,0\,} \\ \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{6}{70} \\ \begin{matrix} {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$

$\left. \begin{align} & \begin{matrix} 260 \\ 2\,\,\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,06\, \\ & \,\,\,\,6\, \\ & \,\,\, \overline{\,00\,} \\ & \,\,\,\,\,\,\, 0 \\ & \,\,\,\,\,\,\, \overline{0 \,} \,\, \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{2}{130} \\ \begin{matrix} {} \\ {} \\ {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$                      $\left. \begin{align} & \begin{matrix} 480 \\ 4\,\,\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,08\, \\ & \,\,\,\,8\, \\ & \,\,\, \overline{\,00\,} \\ & \,\,\,\,\,\,\, 0 \\ & \,\,\,\,\,\,\, \overline{0 \,} \,\, \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{4}{120} \\ \begin{matrix} {} \\ {} \\ {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$ 

b)

$\left. \begin{align} & \begin{matrix} 490 \\ 49\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,\,\,00\, \\ & \,\,\,\,\,\,0\, \\ & \,\,\, \overline{\,\,\,0\,} \\ \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{7}{70} \\ \begin{matrix} {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$                             $\left. \begin{align} & \begin{matrix} 400 \\ 40\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,\,\,00\, \\ & \,\,\,\,\,\,0\, \\ & \,\,\, \overline{\,\,\,0\,} \\ \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{5}{80} \\ \begin{matrix} {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$

$\left. \begin{align} & \begin{matrix} 361 \\ 3\,\,\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,06\, \\ & \,\,\,\,6\, \\ & \,\,\, \overline{\,01\,} \\ & \,\,\,\,\,\,\, 0 \\ & \,\,\,\,\,\,\, \overline{1 \,} \,\, \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{3}{120} \\ \begin{matrix} {} \\ {} \\ {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$                        $\left. \begin{align} & \begin{matrix} 725 \\ 6\,\,\,\,\, \\ \end{matrix} \\ & \overline{\begin{align} & \,12\, \\ & \,12\, \\ & \,\,\, \overline{\,05\,} \\ & \,\,\,\,\,\,\, 3 \\ & \,\,\,\,\,\,\, \overline{2 \,} \,\, \end{align}} \\ \end{align} \right|\begin{matrix} \dfrac{3}{241} \\ \begin{matrix} {} \\ {} \\ {} \\ {} \\ \end{matrix} \\ {} \\ \end{matrix}$

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