一、口算。
$15×\frac{8}{5}=$
$\frac{33}{10}×\frac{2}{3}=$
$\frac{4}{5}÷(1-\frac{4}{5})=$
$55÷\frac{1}{5}=$
$\frac{7}{8}÷\frac{3}{16}=$
$\frac{1}{3}÷9×\frac{27}{13}=$
$1.75-\frac{3}{4}=$
$\frac{13}{20}+\frac{1}{4}=$
$(1-\frac{1}{5})×\frac{3}{4}=$
$\frac{4}{3}÷\frac{16}{15}=$
$\frac{9}{32}÷\frac{3}{16}=$
$\frac{6}{5}÷(7-\frac{5}{6}-\frac{1}{6})=$
$\frac{1}{18}×24=$
$2.7÷\frac{9}{4}=$
$\frac{1}{5}÷\frac{4}{7}-\frac{1}{20}=$
$\frac{7}{4}×\frac{1}{5}=$
$\frac{13}{20}-0.05=$
$\frac{7}{10}+\frac{1}{5}+\frac{1}{10}=$
$\frac{7}{16}×\frac{4}{21}=$
$\frac{5}{8}×\frac{5}{11}=$
$35×(\frac{2}{5}+\frac{1}{7})=$

1.24 2.$\frac{11}{5}$ 3.4 4.275 5.$\frac{14}{3}$ 6.$\frac{1}{13}$ 7.1 8.$\frac{9}{10}$ 9.$\frac{3}{5}$ 10.$\frac{5}{4}$ 11.$\frac{3}{2}$ 12.$\frac{1}{5}$ 13.$\frac{4}{3}$ 14.1.2 15.$\frac{3}{10}$ 16.$\frac{7}{20}$ 17.$\frac{3}{5}$ 18.1 19.$\frac{1}{12}$ 20.$\frac{25}{88}$ 21.19

二、计算下面各题，能用简便算法的就用简便算法。
$(2 + \dfrac{2}{7}) × 35$
$(\dfrac{7}{9} - \dfrac{5}{18}) ÷ (\dfrac{1}{6} + \dfrac{2}{3})$
$\dfrac{11}{23} ÷ 11 × \dfrac{46}{5} + \dfrac{8}{5}$
$\dfrac{1}{8} ÷ [\dfrac{1}{25} × (\dfrac{2}{5} + \dfrac{1}{10})]$
$\dfrac{4}{7} × [\dfrac{1}{2} × (\dfrac{6}{5} - \dfrac{7}{10})]$
$\dfrac{3}{14} × [7 - 4 ÷ (\dfrac{2}{15} + \dfrac{2}{3})]$

1.80 2.$\frac{3}{5}$ 3.2 4.$\frac{25}{4}$ 5.$\frac{1}{7}$ 6.$\frac{3}{7}$