1) ( \frac{7}{15} - \frac{1}{6} )+ \frac{2}{5} = \frac{3}{10}+ \frac{2}{5} = \frac{7}{10}
3)( \frac{8}{9} - \frac{5}{6} )+ \frac{2}{3} = \frac{1}{18} + \frac{2}{3} = \frac{13}{18}
5) (\frac{7}{18} - \frac{1}{12} )+ \frac{5}{6} = \frac{11}{36} + \frac{5}{6} = \frac{41}{36} =1 \frac{5}{36} [/tex]