a) Ta có: \(\dfrac{17}{6}-3\dfrac{2}{5}+\dfrac{5}{-6}\)
\(=\dfrac{17}{6}-\dfrac{17}{5}-\dfrac{5}{6}\)
\(=2-\dfrac{17}{5}=\dfrac{-7}{5}\)
b) Ta có: \(\dfrac{-3}{5}\cdot\dfrac{4}{9}+\dfrac{3}{-5}\cdot1\dfrac{5}{9}+\dfrac{1}{5}\)
\(=\dfrac{-3}{5}\cdot\dfrac{4}{9}+\dfrac{-3}{5}\cdot\dfrac{14}{9}+\dfrac{1}{5}\)
\(=\dfrac{-3}{5}\left(\dfrac{4}{9}+\dfrac{14}{9}\right)+\dfrac{1}{5}\)
\(=\dfrac{-6}{5}+\dfrac{1}{5}=-1\)
c) Ta có: \(\left(\dfrac{2}{3}\cdot\dfrac{7}{5}-\dfrac{2}{5}\cdot\dfrac{2}{3}\right):\left(-\dfrac{1}{6}+\dfrac{10}{12}\right)\)
\(=\left[\dfrac{2}{3}\left(\dfrac{7}{5}-\dfrac{2}{5}\right)\right]:\left(\dfrac{-2}{12}+\dfrac{10}{12}\right)\)
\(=\dfrac{2}{3}:\dfrac{2}{3}\)
\(=\dfrac{2}{3}\cdot\dfrac{3}{2}=1\)
d) Ta có: \(\left(4+\dfrac{3}{5}\right)\cdot\dfrac{17}{8}+\left(2+\dfrac{7}{8}\right):\dfrac{5}{23}\)
\(=\dfrac{23}{5}\cdot\dfrac{17}{8}+\dfrac{23}{8}\cdot\dfrac{23}{5}\)
\(=\dfrac{23}{5}\left(\dfrac{17}{8}+\dfrac{23}{8}\right)\)
\(=\dfrac{23}{5}\cdot5=23\)
e) Ta có: \(\dfrac{3}{4}\cdot\dfrac{-11}{9}-\dfrac{11}{2}\cdot\dfrac{1}{4}-\dfrac{11}{6}\cdot\dfrac{1}{4}\)
\(=\dfrac{3}{9}\cdot\dfrac{-11}{4}-\dfrac{11}{4}\cdot\dfrac{1}{2}-\dfrac{11}{4}\cdot\dfrac{1}{6}\)
\(=\dfrac{-11}{4}\left(\dfrac{1}{3}+\dfrac{1}{2}+\dfrac{1}{6}\right)\)
\(=-\dfrac{11}{4}\cdot\left(\dfrac{2}{6}+\dfrac{3}{6}+\dfrac{1}{6}\right)=-\dfrac{11}{4}\)
g) Ta có: \(37\%-\dfrac{33}{4}:3\dfrac{2}{3}+1.88\)
\(=\dfrac{37}{100}+\dfrac{188}{100}-\dfrac{33}{4}:\dfrac{11}{3}\)
\(=\dfrac{9}{4}-\dfrac{33}{4}\cdot\dfrac{3}{11}\)
\(=\dfrac{9}{4}-\dfrac{9}{4}=0\)
