Tính 11/30+18/35.(35/54-49/18-28/48)

* Hướng dẫn giải

$\frac{11}{30}+\frac{18}{35}.\left(\frac{35}{54}-\frac{49}{18}-\frac{28}{48}\right)=\frac{11}{30}+\left(\frac{18}{35}.\frac{35}{54}-\frac{18}{35}.\frac{49}{18}-\frac{18}{35}.\frac{28}{48}\right)$

$=\frac{11}{30}+\left(\frac{1}{3}-\frac{7}{5}-\frac{3}{10}\right)=\frac{11}{30}+\frac{-41}{30}=-1$