Theo bài ra , ta có :
\(\frac{4}{5}\times\frac{5+\frac{5}{17}+\frac{5}{19}+\frac{5}{2003}}{4+\frac{4}{17}+\frac{4}{19}+\frac{4}{2003}}\)
\(=\frac{4}{5}\times\frac{5\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{2003}\right)}{4\left(\frac{1}{17}+\frac{1}{19}+\frac{1}{2003}\right)}\)
\(=\frac{4}{5}\times\frac{5}{4}\)
\(=1\)
Chúc bạn học tốt
\(\frac{4}{5}.\frac{5+\frac{5}{17}+\frac{5}{19}+\frac{5}{2003}}{4+\frac{4}{17}+\frac{4}{19}+\frac{4}{2003}}=\frac{4}{5}.\frac{5\left(1+\frac{1}{17}+\frac{1}{19}+\frac{1}{2003}\right)}{4\left(1+\frac{1}{17}+\frac{1}{19}+\frac{1}{2003}\right)}=\frac{4}{5}.\frac{5}{4}=1\)