\[\boxed{\mathbf{743\ (743)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ \frac{7}{18} + \frac{5}{18} = \frac{7 + 5}{18} = \frac{12}{18}\]
\[2)\ \frac{11}{24} + \frac{8}{24} = \frac{11 + 8}{24} = \frac{19}{24}\]
\[3)\ \frac{23}{47} - \frac{11}{47} = \frac{23 - 14}{47} = \frac{9}{47}\]
\[4)\ \frac{31}{58} - \frac{16}{58} = \frac{31 - 16}{58} = \frac{15}{58}\]
\[5)\ \frac{3}{29} + \frac{6}{29} - \frac{8}{29} = \frac{3 + 6 - 8}{29} =\]
\[= \frac{1}{29}\]
\[6)\ \frac{29}{64} - \frac{14}{64} - \frac{9}{64} =\]
\[= \frac{29 - 14 - 9}{64} = \frac{6}{64}\]