\(a,3,5.\left(-1\dfrac{2}{5}\right)=\dfrac{7}{2}.\left(\dfrac{-7}{5}\right)=\dfrac{-49}{10}\)
\(b,\dfrac{-5}{23}:\left(-2\right)=\dfrac{-5}{23}.\dfrac{-1}{2}=\dfrac{5}{46}\)
Hôctot
a)=3,5.(-7/5)=7/2.(-7/5)=-49/10
b)=-5/23.(-1/2)=5/46
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