Giải bài 1 trang 83 - SGK Toán lớp 4

Đặt tính rồi tính:

a) 855: 45 
    579 : 36
 b) 9009 : 33
    9276 : 39                             
Lời giải:
a) \(\left. \begin{align} & \begin{matrix} 855\\ \,\underline{45} \,\,\,\,\, \\ \end{matrix} \\\,&\,\,405\\&\,\,\underline{405}\\\,&\,\,\,\,\,\,\,0\end{align} \right|\begin{matrix} \dfrac{\,\,\,\,45\,\,\,\,\,\,\,}{19\,\,} {} \\ {} \\\\\\\end{matrix} \)\(\left. \begin{align} & \begin{matrix} 579\\ \,\underline{36} \,\,\,\,\, \\ \end{matrix} \\\,&\,\,219\\&\,\,\underline{216}\\\,&\,\,\,\,\,\,\,3\end{align} \right|\begin{matrix} \dfrac{\,\,\,\,36\,\,\,\,\,\,\,}{16\,\,} {} \\ {}\\\\\\\end{matrix} \)                               
 
b) \(\left. \begin{align} & \begin{matrix} 9009\\ \,\underline{66}\,\, \,\,\,\,\, \\ \end{matrix} \\\,&\,\,240\\&\,\,\underline{231}\\\,&\,\,\,\,\,\,\,99\\&\,\,\,\,\,\,\,\underline{99}\\\,&\,\,\,\,\,\,\,\,\,\,0\end{align} \right|\begin{matrix} \dfrac{\,\,\,\,33\,\,\,\,\,\,\,}{273\,\,} {} \\ {}\\\\\\\\\\\end{matrix} \)\(\left. \begin{align} & \begin{matrix} 9276\\ \,\underline{78}\,\, \,\,\,\,\, \\ \end{matrix} \\\,&\,\,147\\&\,\,\underline{117}\\\,&\,\,\,\,\,306\\&\,\,\,\,\,\underline{273}\\\,&\,\,\,\,\,\,\,\,33\end{align} \right|\begin{matrix} \dfrac{\,\,\,\,39\,\,\,\,\,\,\,}{237\,\,} {} \\ {}\\\\\\\\\\\end{matrix} \)                                 
 
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