Найди значения выражений: 2/7 + 5/8 + 1/2; 1/2 − 2/15 + 3/5; 6/7 − 1/6 + 2/9.

1. \(\frac{2}{7}+\frac{5}{8}+\frac{1}{2}=\frac{16}{56}+\frac{35}{56}+\frac{28}{56}=\frac{79}{56}=1\frac{23}{56}\).

2. \(\frac{1}{2}-\frac{2}{15}+\frac{3}{5}=\frac{15}{30}-\frac{4}{30}+\frac{18}{30}=\frac{29}{30}\).

3. \(\frac{6}{7}-\frac{1}{6}+\frac{2}{9}=\frac{108}{126}-\frac{21}{126}+\frac{28}{126}=\frac{115}{126}\).

Ответ: 1 23/56; 29/30; 115/126.