1. 直接写出得数。(20☆)
$\frac{5}{8} - \frac{3}{8} =$
$\frac{7}{17} + \frac{10}{17} =$
$\frac{2}{5} + \frac{1}{5} =$
$1 - \frac{9}{14} =$
$\frac{3}{4} - \frac{1}{4} =$
$\frac{5}{13} + \frac{6}{13} =$
$2 - \frac{2}{3} =$
$\frac{1}{12} + \frac{3}{4} =$
$\frac{8}{9} - \frac{1}{9} =$
$1 - \frac{1}{3} =$
$\frac{2}{7} + \frac{5}{7} =$
$\frac{5}{6} + 2 =$
$\frac{1}{4} + \frac{1}{3} =$
$\frac{1}{5} - \frac{1}{7} =$
$\frac{1}{5} + \frac{1}{8} =$
$\frac{3}{4} + \frac{4}{9} - \frac{3}{4} =$
$1 - \frac{7}{12} =$
$\frac{1}{9} + \frac{1}{4} =$
$\frac{1}{9} - \frac{1}{11} =$
$\frac{4}{5} + \frac{7}{10} + \frac{1}{5} =$
$\frac{4}{5} - \frac{3}{4} =$
$\frac{3}{10} + \frac{17}{10} =$
$\frac{2}{3} + \frac{2}{9} =$
$\frac{11}{15} + \frac{2}{5} =$
$\frac{7}{8} - \frac{3}{4} =$
$\frac{4}{15} + \frac{8}{15} =$
$3 - \frac{3}{5} =$
$\frac{2}{7} - \frac{1}{4} + \frac{5}{7} =$
$0 + \frac{3}{4} =$
$\frac{1}{3} - \frac{1}{7} =$
$\frac{7}{10} + \frac{1}{5} =$
$\frac{1}{3} + \frac{4}{9} - \frac{1}{3} =$
$\frac{4}{5} + 0.4 =$
$\frac{7}{10} - \frac{1}{6} =$
$\frac{7}{8} + \frac{1}{6} =$
$\frac{11}{7} + \frac{5}{9} + \frac{4}{9} =$
$\frac{2}{3} + \frac{4}{9} =$
$\frac{7}{15} - \frac{11}{30} =$
$\frac{3}{8} + \frac{5}{16} =$
$\frac{1}{2} + \frac{5}{8} - \frac{5}{8} =$

1. $\frac{1}{4}$ 1 $\frac{3}{5}$ $\frac{5}{14}$
$\frac{1}{2}$ $\frac{11}{13}$ $1\frac{1}{3}$ $\frac{5}{6}$
$\frac{7}{9}$ $\frac{2}{3}$ 1 $2\frac{5}{6}$
$\frac{7}{12}$ $\frac{2}{35}$ $\frac{13}{40}$ $\frac{4}{9}$
$\frac{5}{12}$ $\frac{13}{36}$ $\frac{2}{99}$ $1\frac{7}{10}$
$\frac{1}{20}$ 2 $\frac{8}{9}$ $\frac{17}{15}$
$\frac{1}{8}$ $\frac{4}{5}$ $2\frac{2}{5}$ $\frac{3}{4}$
$\frac{3}{4}$ $\frac{4}{21}$ $\frac{9}{10}$ $\frac{4}{9}$
$\frac{6}{5}$ $\frac{8}{15}$ $\frac{25}{24}$ $2\frac{4}{7}$
$\frac{10}{9}$ $\frac{1}{10}$ $\frac{11}{16}$ $\frac{1}{2}$

2. 计算下面各题,能简算的要简算。(24☆)
$\frac{8}{9} - (\frac{1}{6} + \frac{1}{3})$
$\frac{13}{28} + \frac{5}{17} + \frac{15}{28} + \frac{12}{17}$
$\frac{13}{9} - (\frac{4}{9} + \frac{1}{8})$
$\frac{4}{11} - \frac{6}{7} + \frac{2}{7} + \frac{7}{11}$
$\frac{5}{12} - \frac{1}{18} + \frac{7}{12}$
$\frac{17}{20} - (\frac{7}{20} - \frac{2}{9})$

2. $\frac{7}{18}$ 2 $\frac{7}{8}$ $\frac{3}{7}$ $\frac{17}{18}$ $\frac{13}{18}$