$\frac{3}{8} ÷ \frac{3}{5} =$
$9 × \frac{8}{27} =$
$18 ÷ \frac{15}{8} =$
$\frac{2}{9} × \frac{4}{3} =$
$\frac{5}{14} ÷ \frac{6}{7} =$
$14 ÷ \frac{7}{11} =$
$\frac{3}{25} × 35 =$
$\frac{11}{13} ÷ 11 =$
$\frac{8}{19} ÷ \frac{16}{19} =$
$\frac{11}{8} ÷ \frac{1}{4} =$
$\frac{7}{10} ÷ 5 =$
$1.2 ÷ \frac{4}{7} =$
$\frac{16}{7} ÷ \frac{4}{7} =$
$\frac{8}{63} ÷ \frac{4}{21} =$
$\frac{1}{4} ÷ 2.5 =$
$\frac{3}{4} ÷ \frac{2}{3} =$
$\frac{23}{32} ÷ \frac{23}{4} =$
$\frac{38}{9} ÷ \frac{19}{18} =$
$\frac{5}{12} ÷ \frac{6}{25} =$
$\frac{4}{7} ÷ \frac{2}{5} =$
$6 × \frac{5}{4} =$
$\frac{1}{3} - \frac{1}{5} =$
$\frac{7}{8} ÷ \frac{7}{10} =$
$( \frac{1}{4} + \frac{1}{2} ) × 4 =$

1. $\frac{5}{8}$ $\frac{8}{3}$ $\frac{48}{5}$ $\frac{8}{27}$ $\frac{5}{12}$ 22 $\frac{21}{5}$ $\frac{1}{13}$ $\frac{1}{2}$ $\frac{11}{2}$ $\frac{7}{50}$ 2.1 4 $\frac{2}{3}$ $\frac{1}{10}$ $\frac{9}{8}$ $\frac{1}{8}$ 4 $\frac{125}{72}$ $\frac{10}{7}$ $\frac{15}{2}$ $\frac{2}{15}$ $\frac{5}{4}$ 3

2 脱式计算（能简算的要简算） 建议用时4分钟 评价：☆☆☆
$\frac{9}{16}÷(\frac{3}{8}+\frac{1}{16})$
$\frac{7}{12}÷\frac{1}{6}-\frac{5}{12}×6$
$(\frac{5}{8}+\frac{3}{4})÷\frac{5}{16}$
$\frac{3}{10}×8+\frac{12}{25}$
$\frac{3}{5}÷(\frac{3}{10}+\frac{7}{10}÷\frac{5}{6})$
$\frac{2}{7}×(\frac{5}{9}-\frac{1}{3})÷\frac{4}{21}$

2. $\frac{9}{7}$ 1 $\frac{22}{5}$ $\frac{72}{25}$ $\frac{10}{19}$ $\frac{1}{3}$

某班学生在一次“一分钟跳绳”练习中的平均成绩是158下，如果把它记作0下，超过的数量记作正数，低于的数量记作负数。 涛涛跳了173下记作（）下，明明跳的数量记作－9下，明明跳了（）下。

3. +15 149