三、计算下面各题,怎样简便就怎样计算。
$(\frac {7}{11}-\frac {3}{8})×88$
$5-\frac {7}{8}-\frac {1}{8}$
$\frac {6}{7}×\frac {5}{8}+\frac {3}{8}÷\frac {7}{6}$
$(\frac {3}{5}-\frac {1}{2})×\frac {5}{3}+\frac {2}{9}$
$\frac {7}{9}÷\frac {13}{5}+\frac {5}{9}×\frac {2}{13}$
$\frac {8}{15}×\frac {5}{4}-\frac {1}{6}÷\frac {1}{3}$
$\frac {4}{5}×\frac {10}{3}-\frac {4}{5}×\frac {7}{3}$
$(\frac {9}{10}+\frac {3}{5})×(\frac {2}{9}-\frac {2}{15})$
$\frac {2}{3}-(\frac {1}{6}+\frac {1}{4})÷\frac {3}{4}$
$\frac {8}{9}×\frac {3}{4}÷(\frac {1}{3}+\frac {1}{5})$
$\frac {3}{5}÷3+\frac {1}{3}×\frac {1}{5}$
$12÷[(\frac {7}{9}-\frac {2}{3})×\frac {9}{10}]$
$(1-\frac {1}{4}×\frac {8}{9})÷\frac {7}{9}$
$\frac {3}{5}÷[(\frac {1}{5}+\frac {1}{3})÷\frac {2}{9}]$
$\frac {8}{49}÷[\frac {9}{8}-(\frac {1}{8}+\frac {3}{7})]$

三、$23$ $4$ $\frac{6}{7}$ $\frac{7}{18}$ $\frac{5}{13}$ $\frac{1}{6}$ $\frac{4}{5}$ $\frac{2}{15}$ $\frac{1}{9}$ $\frac{5}{4}$ $\frac{4}{15}$ $120$ $1$ $\frac{1}{4}$ $\frac{2}{7}$

1. $(\frac{7}{11} - \frac{3}{8})×88$
$=\frac{7}{11}×88 - \frac{3}{8}×88$
$=56 - 33$
$=23$
2. $5 - \frac{7}{8} - \frac{1}{8}$
$=5 - (\frac{7}{8} + \frac{1}{8})$
$=5 - 1$
$=4$
3. $\frac{6}{7}×\frac{5}{8} + \frac{3}{8}÷\frac{7}{6}$
$=\frac{6}{7}×\frac{5}{8} + \frac{3}{8}×\frac{6}{7}$
$=\frac{6}{7}×(\frac{5}{8} + \frac{3}{8})$
$=\frac{6}{7}×1$
$=\frac{6}{7}$
4. $(\frac{3}{5} - \frac{1}{2})×\frac{5}{3} + \frac{2}{9}$
$=(\frac{6}{10} - \frac{5}{10})×\frac{5}{3} + \frac{2}{9}$
$=\frac{1}{10}×\frac{5}{3} + \frac{2}{9}$
$=\frac{1}{6} + \frac{2}{9}$
$=\frac{3}{18} + \frac{4}{18}$
$=\frac{7}{18}$
5. $\frac{7}{9}÷\frac{13}{5} + \frac{5}{9}×\frac{2}{13}$
$=\frac{7}{9}×\frac{5}{13} + \frac{5}{9}×\frac{2}{13}$
$=\frac{35}{117} + \frac{10}{117}$
$=\frac{45}{117}$
$=\frac{5}{13}$
6. $\frac{8}{15}×\frac{5}{4} - \frac{1}{6}÷\frac{1}{3}$
$=\frac{2}{3} - \frac{1}{6}×3$
$=\frac{2}{3} - \frac{1}{2}$
$=\frac{4}{6} - \frac{3}{6}$
$=\frac{1}{6}$
7. $\frac{4}{5}×\frac{10}{3} - \frac{4}{5}×\frac{7}{3}$
$=\frac{4}{5}×(\frac{10}{3} - \frac{7}{3})$
$=\frac{4}{5}×1$
$=\frac{4}{5}$
8. $(\frac{9}{10} + \frac{3}{5})×(\frac{2}{9} - \frac{2}{15})$
$=(\frac{9}{10} + \frac{6}{10})×(\frac{10}{45} - \frac{6}{45})$
$=\frac{15}{10}×\frac{4}{45}$
$=\frac{3}{2}×\frac{4}{45}$
$=\frac{12}{90}$
$=\frac{2}{15}$
9. $\frac{2}{3} - (\frac{1}{6} + \frac{1}{4})÷\frac{3}{4}$
$=\frac{2}{3} - (\frac{2}{12} + \frac{3}{12})×\frac{4}{3}$
$=\frac{2}{3} - \frac{5}{12}×\frac{4}{3}$
$=\frac{2}{3} - \frac{5}{9}$
$=\frac{6}{9} - \frac{5}{9}$
$=\frac{1}{9}$
10. $\frac{8}{9}×\frac{3}{4}÷(\frac{1}{3} + \frac{1}{5})$
$=\frac{2}{3}÷(\frac{5}{15} + \frac{3}{15})$
$=\frac{2}{3}÷\frac{8}{15}$
$=\frac{2}{3}×\frac{15}{8}$
$=\frac{30}{24}$
$=\frac{5}{4}$
11. $\frac{3}{5}÷3 + \frac{1}{3}×\frac{1}{5}$
$=\frac{3}{5}×\frac{1}{3} + \frac{1}{15}$
$=\frac{1}{5} + \frac{1}{15}$
$=\frac{3}{15} + \frac{1}{15}$
$=\frac{4}{15}$
12. $12÷[(\frac{7}{9} - \frac{2}{3})×\frac{9}{10}]$
$=12÷[(\frac{7}{9} - \frac{6}{9})×\frac{9}{10}]$
$=12÷[\frac{1}{9}×\frac{9}{10}]$
$=12÷\frac{1}{10}$
$=12×10$
$=120$
13. $(1 - \frac{1}{4}×\frac{8}{9})÷\frac{7}{9}$
$=(1 - \frac{2}{9})×\frac{9}{7}$
$=\frac{7}{9}×\frac{9}{7}$
$=1$
14. $\frac{3}{5}÷[(\frac{1}{5} + \frac{1}{3})÷\frac{2}{9}]$
$=\frac{3}{5}÷[(\frac{3}{15} + \frac{5}{15})×\frac{9}{2}]$
$=\frac{3}{5}÷[\frac{8}{15}×\frac{9}{2}]$
$=\frac{3}{5}÷\frac{12}{5}$
$=\frac{3}{5}×\frac{5}{12}$
$=\frac{1}{4}$
15. $\frac{8}{49}÷[\frac{9}{8} - (\frac{1}{8} + \frac{3}{7})]$
$=\frac{8}{49}÷[\frac{9}{8} - \frac{1}{8} - \frac{3}{7}]$
$=\frac{8}{49}÷[1 - \frac{3}{7}]$
$=\frac{8}{49}÷\frac{4}{7}$
$=\frac{8}{49}×\frac{7}{4}$
$=\frac{2}{7}$