\(a,25.125.32.7=3125.32.7=100000.7=700000\)
\(b,15.\left(-7\right)+15.\left(-3\right)=15.\left[\left(-7\right)+\left(-3\right)\right]=15.\left(-10\right)=-150\)
\(c,\left(\dfrac{3}{4}+\dfrac{-7}{2}\right).\left(\dfrac{2}{11}+\dfrac{6}{11}\right)=\left(\dfrac{6}{8}+\dfrac{-28}{8}\right).\dfrac{8}{11}=\left(\dfrac{-22}{8}\right).\dfrac{8}{11}=\dfrac{-176}{88}=-2\)
\(d,2\dfrac{3}{4}.\left(-0,4\right)-1\dfrac{3}{5}.2,75+\left(-1,2\right):\dfrac{4}{11}\)
\(=\dfrac{11}{4}.\left(-\dfrac{2}{5}\right)-\dfrac{8}{5}.\dfrac{11}{4}+\left(-\dfrac{6}{5}\right):\dfrac{4}{11}=\left(-\dfrac{11}{10}\right)-\dfrac{22}{5}+\left(-\dfrac{33}{10}\right)\)
\(=\left(-\dfrac{11}{2}\right)+\left(-\dfrac{33}{10}\right)=-\dfrac{44}{5}\)
\(e,\dfrac{42}{46}+\dfrac{250}{286}+\dfrac{-2121}{2323}+\dfrac{-125125}{143143}=\dfrac{21}{23}+\dfrac{125}{143}+\left(-\dfrac{21}{23}\right)+\left(-\dfrac{125}{143}\right)\)
\(=\left[\dfrac{21}{23}+\left(-\dfrac{21}{23}\right)\right]+\left[\dfrac{125}{143}+\left(-\dfrac{125}{143}\right)\right]=0+0=0\)
