Bài 1; Tính
a)\(\left(\dfrac{5}{18}-\dfrac{7}{24}+\dfrac{1}{9}\right):\dfrac{7}{18}\)
b)\(\left(\dfrac{7}{20}-\dfrac{5}{16}+\dfrac{3}{40}\right):\left(\dfrac{4}{15}-\dfrac{3}{10}+\dfrac{1}{12}\right)\)
Bài 2:Tìm x
a)\(\dfrac{3}{10}-x=\dfrac{5}{6}-\dfrac{2}{15}\)
b)\(\dfrac{-5}{8}+x=\dfrac{4}{9}-\dfrac{7}{1}\)
c)\(\dfrac{2}{x-3}=\dfrac{x-3}{18}\)
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