Rút gọn biểu thức. {1 + 2/3+ 3/5 + (4/7))/2 + 4/3 + 6/5+ 8/7

\(\frac{{1 + \frac{2}{3} + \frac{3}{5} + \frac{4}{7}}}{{2 + \frac{4}{3} + \frac{6}{5} + \frac{8}{7}}} = \) \(\frac{{1 + \frac{2}{3} + \frac{3}{5} + \frac{4}{7}}}{{2 \times 1 + 2 \times \frac{2}{3} + 2 \times \frac{3}{5} + 2 \times \frac{4}{7}}} = \)\(\frac{{1 + \frac{2}{3} + \frac{3}{5} + \frac{4}{7}}}{{2 \times \left( {1 + \frac{2}{3} + \frac{3}{5} + \frac{4}{7}} \right)}} = \frac{1}{2}\)