a: \(=\dfrac{-10}{13}-\dfrac{3}{13}+\dfrac{5}{17}+\dfrac{12}{17}-\dfrac{11}{20}\)
=-11/20
b: \(=\dfrac{9}{12}-\dfrac{10}{12}+\dfrac{11}{12}=\dfrac{10}{12}=\dfrac{5}{6}\)
c: \(=\left[-10+9\right]\cdot15=-15\)
d: \(=\dfrac{5}{4}\cdot\dfrac{4}{3}+\left(\dfrac{1}{4}-\dfrac{5}{6}\right):\dfrac{14}{3}\)
\(=\dfrac{5}{3}+\dfrac{-7}{12}\cdot\dfrac{3}{14}=\dfrac{5}{3}-\dfrac{1}{8}=\dfrac{37}{24}\)
a). \(\dfrac{-10}{13}+\dfrac{5}{17}-\dfrac{3}{13}+\dfrac{12}{17}-\dfrac{11}{20}\)
\(=\left(\dfrac{-10}{13}-\dfrac{3}{13}\right)+\left(\dfrac{5}{17}+\dfrac{12}{17}\right)-\dfrac{11}{20}\)
\(=\dfrac{-13}{13}+\dfrac{17}{17}-\dfrac{11}{20}\)
\(=\left(-1\right)+1-\dfrac{11}{20}\)
\(=0-\dfrac{11}{20}\)
\(=\dfrac{-11}{20}\)
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b). \(\dfrac{3}{4}+\dfrac{-5}{6}-\dfrac{11}{-12}\)
\(=\dfrac{3}{4}+\dfrac{-5}{6}-\dfrac{-11}{12}\)
\(=\dfrac{9}{12}+\dfrac{-10}{12}+\dfrac{11}{12}\)
\(=\dfrac{10}{12}=\dfrac{5}{6}\)
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c). \(\left[\left(-0,2\right):0,02+9\right]\left(1,5\times2,7+1,5\times7,3\right)\)
\(=\left[\left(-10\right)+9\right].\left[15\times\left(2,7+7,3\right)\right]\)
\(=\left(-1\right)\times\left[15\times10\right]\)
\(=\left(-1\right)\times150\)
\(=-150\)
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d). \(1,25:\dfrac{15}{20}+\left(25\%-\dfrac{5}{6}\right):4\dfrac{2}{3}\)
\(=\dfrac{125}{100}:\dfrac{15}{20}+\left(\dfrac{25}{100}-\dfrac{5}{6}\right):\dfrac{14}{3}\)
\(=\dfrac{5}{4}:\dfrac{3}{4}+\left(\dfrac{1}{4}-\dfrac{5}{6}\right):\dfrac{14}{3}\) ( đoạn này rút gọn nha )
\(=\dfrac{5}{4}:\dfrac{3}{4}+\left(\dfrac{3}{12}-\dfrac{10}{12}\right):\dfrac{14}{3}\)
\(=\dfrac{5}{4}:\dfrac{3}{4}+\dfrac{-7}{12}:\dfrac{14}{3}\)
\(=\dfrac{5}{4}\times\dfrac{4}{3}+\dfrac{-7}{12}:\dfrac{14}{3}\)
\(=\dfrac{5}{3}+\dfrac{-7}{12}\times\dfrac{3}{14}\)
\(=\dfrac{5}{3}+\dfrac{-1}{8}\)
\(=\dfrac{40}{24}+\dfrac{-3}{24}\)
\(=\dfrac{37}{24}\)
