Giải bài 2 trang 177 - SGK Toán lớp 4

a) $\dfrac{\begin{align} & \,\,\,\,24579\\ & + \\ & \,\,\,\, 43867\,\,\\ \end{align}}{\,\,\,\,68446}$                           $\dfrac{\begin{align} & \,\,\,\,82604\\ & -\\ & \,\,\,\, 35246\\ \end{align}}{\,\,\,47358}$ 

b) $\dfrac{\begin{align} & \,\,\,\,\,235\\ & \times \\ & \,\,\,\,\,325\,\,\,\, \\ \end{align}}{\,\,1175}\\\,\,\,\,470\,\\\underline{\,705\,\,\,\,\,\,\,\,\,\,\,\,}\\\,76375$                          $\left. \begin{align} & \begin{matrix} 101598\\ \,\,\,\,1549\,\,\,\,\, \\ \end{matrix} \\ & \,\,\,\,\,\,\,1148\\ & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,0\\\\\ \end{align} \right|\begin{matrix} \dfrac{\,\,\,\,287\,\,\,\,\,\,\,}{354\,\,} {} \\ {} \\ \\\\\\\end{matrix}$