一、口算。
$\frac{8}{15} × \frac{3}{2} =$
$\frac{2}{3} ÷ \frac{3}{4} =$
$12 × \frac{2}{3} =$
$\frac{9}{4} - \frac{7}{8} =$
$\frac{4}{5} ÷ \frac{1}{2} =$
$\frac{11}{16} ÷ 22 =$
$\frac{2}{13} ÷ 4 =$
$\frac{7}{6} - \frac{1}{4} =$
$\frac{5}{6} × \frac{2}{5} =$
$\frac{1}{4} ÷ \frac{3}{5} =$
$\frac{5}{8} × \frac{14}{15} =$
$\frac{6}{5} ÷ \frac{8}{75} =$
$\frac{7}{12} × \frac{4}{7} =$
$\frac{6}{7} ÷ \frac{2}{3} =$
$\frac{9}{20} × \frac{10}{27} =$
$14 × \frac{5}{7} =$
$\frac{3}{2} ÷ \frac{5}{7} =$
$24 ÷ \frac{2}{3} =$
$\frac{1}{7} ÷ \frac{1}{2} =$
$\frac{8}{25} × \frac{5}{16} =$
$\frac{3}{28} ÷ \frac{2}{7} =$

1.$\frac{4}{5}$ 2.$\frac{8}{9}$ 3.$8$ 4.$\frac{11}{8}$ 5.$\frac{8}{5}$ 6.$\frac{1}{32}$ 7.$\frac{1}{26}$ 8.$\frac{11}{12}$ 9.$\frac{1}{3}$ 10.$\frac{5}{12}$ 11.$\frac{7}{12}$ 12.$\frac{45}{4}$ 13.$\frac{1}{3}$ 14.$\frac{9}{7}$ 15.$\frac{1}{6}$ 16.$10$ 17.$\frac{21}{10}$ 18.$36$ 19.$\frac{2}{7}$ 20.$\frac{1}{10}$ 21.$\frac{3}{8}$

二、计算下面各题，能用简便算法的就用简便算法。
$\frac{25}{24} ÷ \frac{5}{8} ÷ \frac{5}{6}$
$\frac{3}{2} ÷ \frac{1}{6} × \frac{25}{8} ÷ \frac{5}{4}$
$\frac{11}{9} ÷ \frac{3}{4} + \frac{7}{9} ÷ \frac{3}{4}$
$\frac{9}{4} × ( \frac{5}{8} ÷ \frac{27}{32} )$
$\frac{9}{11} ÷ \frac{4}{3} + \frac{13}{11} × 0.75$
$( \frac{7}{15} + \frac{4}{5} ÷ 6 ) ÷ \frac{24}{11}$

1.$2$ 2.$\frac{45}{2}$ 3.$\frac{8}{3}$ 4.$\frac{5}{3}$ 5.$\frac{3}{2}$ 6.$\frac{11}{40}$