二、计算下面各题,怎样简便就怎样计算。
$24×\frac {51}{43}+51×\frac {19}{43}$ $\frac {3}{4}-\frac {3}{4}÷3+\frac {9}{25}$ $\frac {5}{6}-82\% -18\% +\frac {1}{6}$
$\frac {4}{5}×\frac {4}{8}×\frac {5}{4}-\frac {1}{3}$ $(\frac {1}{6}+\frac {7}{15})÷\frac {2}{5}+\frac {5}{12}$ $\frac {5}{13}÷7+\frac {1}{7}×\frac {9}{13}$
$\frac {5}{9}×6+\frac {4}{9}÷\frac {1}{6}$ $\frac {14}{9}×\frac {11}{10}-\frac {5}{9}×\frac {11}{10}$ $[1-(\frac {1}{4}+\frac {5}{8})]÷\frac {3}{4}$
$(\frac {1}{4}-\frac {1}{6})×4×6$ $\frac {26}{9}÷\frac {14}{15}×\frac {6}{13}÷\frac {20}{21}$ $25\% ×[(23+2\% )×4]$
$1-\frac {5}{8}÷(\frac {1}{2}+\frac {8}{9})$ $\frac {5}{44}÷[\frac {5}{8}÷(\frac {14}{3}-\frac {1}{2})]$ $(\frac {2}{3}+\frac {1}{4}÷\frac {3}{4})×\frac {1}{4}$

1. $24×\frac {51}{43}+51×\frac {19}{43}$
解：
$=24×\frac {51}{43}+19×\frac {51}{43}$
$=(24 + 19)×\frac {51}{43}$
$=43×\frac {51}{43}$
$=51$
2. $\frac {3}{4}-\frac {3}{4}÷3+\frac {9}{25}$
解：
$=\frac {3}{4}-\frac {3}{4}×\frac {1}{3}+\frac {9}{25}$
$=\frac {3}{4}-\frac {1}{4}+\frac {9}{25}$
$=\frac {1}{2}+\frac {9}{25}$
$=\frac {25}{50}+\frac {18}{50}$
$=\frac {43}{50}$
3. $\frac {5}{6}-82\% -18\% +\frac {1}{6}$
解：
$=(\frac {5}{6}+\frac {1}{6})-(82\% +18\%)$
$=1 - 1$
$=0$
4. $\frac {4}{5}×\frac {4}{8}×\frac {5}{4}-\frac {1}{3}$
解：
$=\frac {4}{5}×\frac {5}{4}×\frac {4}{8}-\frac {1}{3}$
$=1×\frac {1}{2}-\frac {1}{3}$
$=\frac {1}{2}-\frac {1}{3}$
$=\frac {3}{6}-\frac {2}{6}$
$=\frac {1}{6}$
5. $(\frac {1}{6}+\frac {7}{15})÷\frac {2}{5}+\frac {5}{12}$
解：
$=(\frac {5}{30}+\frac {14}{30})×\frac {5}{2}+\frac {5}{12}$
$=\frac {19}{30}×\frac {5}{2}+\frac {5}{12}$
$=\frac {19}{12}+\frac {5}{12}$
$=2$
6. $\frac {5}{13}÷7+\frac {1}{7}×\frac {9}{13}$
解：
$=\frac {5}{13}×\frac {1}{7}+\frac {1}{7}×\frac {9}{13}$
$=(\frac {5}{13}+\frac {9}{13})×\frac {1}{7}$
$=\frac {14}{13}×\frac {1}{7}$
$=\frac {2}{13}$
7. $\frac {5}{9}×6+\frac {4}{9}÷\frac {1}{6}$
解：
$=\frac {5}{9}×6+\frac {4}{9}×6$
$=(\frac {5}{9}+\frac {4}{9})×6$
$=1×6$
$=6$
8. $\frac {14}{9}×\frac {11}{10}-\frac {5}{9}×\frac {11}{10}$
解：
$=(\frac {14}{9}-\frac {5}{9})×\frac {11}{10}$
$=1×\frac {11}{10}$
$=\frac {11}{10}$
9. $[1-(\frac {1}{4}+\frac {5}{8})]÷\frac {3}{4}$
解：
$=[1-(\frac {2}{8}+\frac {5}{8})]×\frac {4}{3}$
$=(1-\frac {7}{8})×\frac {4}{3}$
$=\frac {1}{8}×\frac {4}{3}$
$=\frac {1}{6}$
10. $(\frac {1}{4}-\frac {1}{6})×4×6$
解：
$=\frac {1}{4}×4×6-\frac {1}{6}×4×6$
$=6 - 4$
$=2$
11. $\frac {26}{9}÷\frac {14}{15}×\frac {6}{13}÷\frac {20}{21}$
解：
$=\frac {26}{9}×\frac {15}{14}×\frac {6}{13}×\frac {21}{20}$
$=(\frac {26}{9}×\frac {6}{13})×(\frac {15}{14}×\frac {21}{20})$
$=\frac {4}{3}×\frac {9}{8}$
$=\frac {3}{2}$
12. $25\% ×[(23+2\%)×4]$
解：
$=0.25×4×(23 + 0.02)$
$=1×23.02$
$=23.02$
13. $1-\frac {5}{8}÷(\frac {1}{2}+\frac {8}{9})$
解：
$=1-\frac {5}{8}÷(\frac {9}{18}+\frac {16}{18})$
$=1-\frac {5}{8}÷\frac {25}{18}$
$=1-\frac {5}{8}×\frac {18}{25}$
$=1-\frac {9}{20}$
$=\frac {11}{20}$
14. $\frac {5}{44}÷[\frac {5}{8}÷(\frac {14}{3}-\frac {1}{2})]$
解：
$=\frac {5}{44}÷[\frac {5}{8}÷(\frac {28}{6}-\frac {3}{6})]$
$=\frac {5}{44}÷(\frac {5}{8}÷\frac {25}{6})$
$=\frac {5}{44}÷(\frac {5}{8}×\frac {6}{25})$
$=\frac {5}{44}÷\frac {3}{20}$
$=\frac {5}{44}×\frac {20}{3}$
$=\frac {25}{33}$
15. $(\frac {2}{3}+\frac {1}{4}÷\frac {3}{4})×\frac {1}{4}$
解：
$=(\frac {2}{3}+\frac {1}{4}×\frac {4}{3})×\frac {1}{4}$
$=(\frac {2}{3}+\frac {1}{3})×\frac {1}{4}$
$=1×\frac {1}{4}$
$=\frac {1}{4}$