1. 直接写得数。
$\frac{1}{2} - \frac{1}{5} =$
$4\frac{1}{2} - \frac{1}{2} =$
$2 - \frac{4}{5} =$
$\frac{1}{2} - \frac{1}{4} =$
$\frac{1}{4} + \frac{1}{3} =$
$\frac{1}{14} - \frac{1}{28} =$
$\frac{1}{4} + \frac{1}{4} =$
$\frac{1}{9} + \frac{5}{6} + \frac{8}{9} =$

1. $\frac{3}{10}$ 4 $1\frac{1}{5}$ $\frac{1}{4}$ $\frac{7}{12}$ $\frac{1}{28}$ $\frac{1}{2}$ $1\frac{5}{6}$

2. 用你喜欢的方式计算。
$6 - \frac{4}{15} - \frac{11}{15}$
$\frac{1}{6} + \frac{5}{6} + \frac{8}{15}$
$\frac{1}{4} - \frac{1}{6} - \frac{1}{12}$
$14 + \frac{32}{16} - 1$
$\frac{2}{9} + \frac{3}{9} - 1 + \frac{6}{9} + \frac{1}{3}$
$\frac{2}{3} + \frac{1}{12}$

2. 5 $1\frac{8}{15}$ 0 15 $\frac{5}{9}$ $\frac{3}{4}$

3. 解方程。
$x ÷ 4 = \frac{1}{3}$
$x + \frac{12}{7} = 3$
$x - \frac{2}{5} = \frac{5}{7}$

3. $\frac{4}{3}$ $1\frac{2}{7}$(或$\frac{9}{7}$) $1\frac{4}{35}$(或$\frac{39}{35}$)