c: \(=\dfrac{-2}{13}\left(-\dfrac{1}{4}-\dfrac{7}{24}\right)=\dfrac{-2}{13}\cdot\dfrac{-13}{24}=\dfrac{1}{12}\)
f: \(=\dfrac{3}{7}\left(-\dfrac{1}{27}-\dfrac{5}{9}\right)\)
\(=\dfrac{3}{7}\cdot\dfrac{-1-15}{27}=-\dfrac{16}{27}\cdot\dfrac{3}{7}=\dfrac{-16}{63}\)
`e)([-1]/4).(-2/13)-7/24.(-2/13)`
`=(-2/13).([-1]/4-7/24)`
`=(-2/13).([-6]/24-7/24)`
`=(-2/13).[-13]/24=1/12`
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`f)([-1]/27). 3/7+5/9 .(-3/7)`
`=3/7 .([-1]/27-5/9)`
`=3/7 .([-1]/27-15/27)`
`=3/7 .[-16]/27`
`=-16/63`
\(e,\left(\dfrac{-1}{4}\right).\left(\dfrac{-2}{13}\right)-\dfrac{7}{24}.\left(\dfrac{-2}{13}\right)=\left(\dfrac{-2}{13}\right).\left(\dfrac{-1}{4}-\dfrac{7}{24}\right)=\left(\dfrac{-2}{13}\right).\left(\dfrac{-13}{24}\right)=\dfrac{1}{12}\)
\(f,\left(\dfrac{-1}{27}\right).\dfrac{3}{7}+\left(\dfrac{5}{9}\right).\left(\dfrac{-3}{7}\right)=\dfrac{1}{27}.\left(\dfrac{-3}{7}\right)+\dfrac{5}{9}.\left(\dfrac{-3}{7}\right)=\left(\dfrac{-3}{7}\right).\left(\dfrac{1}{27}+\dfrac{5}{9}\right)=\left(\dfrac{-3}{7}\right).\dfrac{16}{27}=\dfrac{-16}{63}\)
