\(12)\)
\(\sqrt{0,49}.\left(\dfrac{1}{\sqrt{81}}+\dfrac{1}{3}-1\right)+\left(0,4\right)^5.\left(\dfrac{5}{2}\right)^5\)
\(=0,7.\left(\dfrac{1}{9}+\dfrac{1}{3}-1\right)+0,01024.\dfrac{3125}{32}\)
\(=0,7.\left(\dfrac{1}{9}+\dfrac{3}{9}-1\right)+0,01024.\dfrac{3125}{32}\)
\(=0,7.\left(\dfrac{4}{9}-1\right)+0,01024.\dfrac{3125}{32}\)
\(=0,7.\dfrac{-5}{9}+0,01024.\dfrac{3125}{32}\)
\(=\dfrac{-7}{18}+0,01024.\dfrac{3125}{32}\)
\(=\dfrac{-7}{18}+1\)
\(=\dfrac{11}{18}\)
`12,` \(\sqrt{0,49}\cdot\left(\dfrac{1}{\sqrt{81}}+\dfrac{1}{3}-1\right)+\left(0,4\right)^5\cdot\left(\dfrac{5}{2}\right)^5\)
\(=0,7\cdot\left(\dfrac{1}{9}+\dfrac{1}{3}-1\right)+\left(0,4\cdot\dfrac{5}{2}\right)^5\)
\(=0,7\cdot-\dfrac{5}{9}+1\)
`= -7/18+1=11/18`