一、口算。
$\frac{3}{4} ÷ \frac{4}{3} =$
$24\% × 5 =$
$\frac{2}{3} + \frac{5}{12} =$
$200\% × \frac{2}{7} =$
$\frac{6}{7} ÷ \frac{4}{9} =$
$\frac{3}{4} ÷ \frac{3}{16} =$
$\frac{7}{8} × \frac{1}{7} =$
$\frac{7}{5} × \frac{10}{21} =$
$80\% - \frac{2}{5} =$
$6 ÷ \frac{6}{7} =$
$\frac{1}{3} + \frac{3}{4} =$
$10 + 10\% =$
$100\% - \frac{5}{8} =$
$\frac{4}{5} × \frac{3}{4} =$
$\frac{2}{3} ÷ \frac{5}{6} =$
$\frac{3}{5} ÷ \frac{5}{8} =$
$\frac{6}{7} - \frac{2}{3} =$
$\frac{1}{5} × 50\% =$
$\frac{5}{8} + \frac{3}{4} =$
$\frac{2}{7} × 14\% =$
$\frac{14}{19} ÷ \frac{7}{19} =$

1.$\frac{9}{16}$
2.$1.2$
3.$\frac{13}{12}$
4.$\frac{4}{7}$
5.$\frac{27}{14}$
6.$4$
7.$\frac{1}{8}$
8.$\frac{2}{3}$
9.$\frac{2}{5}$
10.$7$
11.$\frac{13}{12}$
12.$10.1$
13.$\frac{3}{8}$
14.$\frac{3}{5}$
15.$\frac{4}{5}$
16.$\frac{24}{25}$
17.$\frac{4}{21}$
18.$\frac{1}{10}$
19.$\frac{11}{8}$
20.$\frac{1}{25}$
21.$2$

二、计算下面各题，能用简便算法的就用简便算法。
$\frac{2}{7} + \frac{3}{8} × \frac{4}{9} + \frac{5}{6}$
$\frac{12}{5} × ( \frac{5}{6} + \frac{3}{4} ) + 52\%$
$\frac{8}{9} × [ 75\% - ( \frac{7}{16} - 25\% ) ]$
$( \frac{1}{2} + \frac{1}{8} ) ÷ 12.5\%$
$( \frac{5}{6} + \frac{1}{2} ) × ( \frac{7}{8} + \frac{1}{2} )$
$( \frac{2}{3} - \frac{5}{8} + \frac{1}{6} ) ÷ \frac{1}{48}$

1.$1\frac{2}{7}$
2.$\frac{108}{25}$
3.$\frac{1}{2}$
4.$5$
5.$\frac{11}{6}$
6.$10$