\(\left[\left(7+\dfrac{1}{250}x\right):\dfrac{9}{10}\right]:\dfrac{247}{10}-12.3=77.7\)
\(\Leftrightarrow\left(x\cdot\dfrac{1}{250}+7\right)=\left(77.7+12.3\right)\cdot\dfrac{247}{10}\cdot\dfrac{9}{10}=2000.7\)
\(\Leftrightarrow x\cdot\dfrac{1}{250}=1993.7\)
\(\Leftrightarrow x=498425\)




