= \(\frac{3}{762}+\frac{1}{417.762}-\frac{1}{139}.\left(4+\frac{761}{762}\right)-\frac{4}{417.762}+\frac{5}{139}\)
= \(\frac{3}{762}+\left(\frac{1}{417.762}-\frac{4}{417.762}\right)-\frac{1}{139}.\left(4+1-\frac{1}{762}\right)+\frac{5}{139}\)
= \(\frac{3}{762}+\frac{-3}{417.762}-\frac{5}{139}+\frac{1}{762.139}+\frac{5}{139}\)
= \(\frac{3}{762}+\left(\frac{-1}{139.762}+\frac{1}{762.139}\right)+\left(-\frac{5}{139}+\frac{5}{139}\right)=\frac{3}{762}=\frac{1}{254}\)