1.直接写出得数。(每题1★)
$\frac{5}{12}÷\frac{1}{12}=$
$\frac{3}{20}÷\frac{1}{7}=$
$\frac{5}{7}÷\frac{1}{4}=$
$\frac{1}{3}÷\frac{1}{9}=$
$0÷\frac{1}{100}=$
$\frac{3}{7}×\frac{1}{3}=$
$\frac{21}{40}÷\frac{7}{8}=$
$\frac{13}{25}÷13=$
$13÷\frac{2}{7}=$
$\frac{15}{16}÷5=$
$\frac{1}{8}÷\frac{5}{2}=$
$\frac{3}{8}÷\frac{6}{7}=$
$4÷\frac{8}{3}=$
$\frac{1}{6}÷\frac{1}{7}=$
$15×\frac{4}{5}=$
$\frac{13}{34}÷\frac{13}{34}=$
$\frac{6}{5}÷\frac{6}{15}=$
$\frac{3}{8}÷\frac{3}{4}=$
$\frac{4}{15}÷\frac{8}{9}=$
$8÷\frac{4}{5}=$

1. $5$ $\frac{21}{20}$ $\frac{20}{7}$ $3$
$0$ $\frac{1}{7}$ $\frac{3}{5}$ $\frac{1}{25}$
$\frac{91}{2}$ $\frac{3}{16}$ $\frac{1}{20}$ $\frac{7}{16}$
$\frac{3}{2}$ $\frac{7}{6}$ $12$ $1$
$3$ $\frac{1}{2}$ $\frac{3}{10}$ $10$

2.计算下面各题,能简算的要简算。(每题3★)
$\frac{9}{15}-(\frac{1}{5}+\frac{1}{3})$
$\frac{3}{11}+\frac{4}{7}+\frac{8}{11}+\frac{3}{7}$
$\frac{5}{8}+\frac{11}{10}-\frac{3}{8}+\frac{9}{10}$

2. $\frac{1}{15}$ $2$ $2\frac{1}{4}$

3.解方程。（每题3★）
$5x=\dfrac{10}{9}$
$0.8x=\dfrac{8}{35}$
$\dfrac{4}{7}x=20$
$\dfrac{5}{7}x=35$
$\dfrac{7}{9}x=\dfrac{49}{72}$
$\dfrac{4}{15}x=\dfrac{2}{5}$

3. $x=\frac{2}{9}$ $x=\frac{2}{7}$ $x=35$
$x=49$ $x=\frac{7}{8}$ $x=\frac{3}{2}$