Răspuns:
1
Explicație pas cu pas:
[tex][0,8-0,(18)\cdot0,1(2)]:0,(7)=\\=(\dfrac{8}{10}-\dfrac{18}{99}\cdot\dfrac{11}{90}):\dfrac{7}{9}=\\=(\dfrac{8}{10}-\dfrac{18\cdot11}{99\cdot90})\cdot\dfrac{9}{7}=\\=(\dfrac{4}{5}-\dfrac{1}{45})\cdot\dfrac{9}{7}=\\=\dfrac{36-1}{45}\cdot\dfrac{9}{7}=\\=\dfrac{35}{5\cdot7}=\\=\dfrac{35}{35}=\\=1[/tex]