1.直接写出得数。（每题1★）
$\frac{5}{9}×4=$
$\frac{8}{27}×2=$
$5×\frac{1}{3}=$
$8×\frac{10}{7}=$
$12×\frac{5}{8}=$
$\frac{2}{7}×\frac{3}{4}=$
$\frac{25}{24}×\frac{16}{15}=$
$\frac{14}{17}×\frac{17}{28}=$
$\frac{7}{9}×\frac{2}{21}=$
$\frac{7}{18}×\frac{9}{14}=$
$\frac{8}{17}×\frac{17}{16}=$
$\frac{7}{11}×\frac{22}{63}=$
$\frac{1}{6}×\frac{3}{7}=$
$\frac{3}{4}×\frac{4}{11}=$
$\frac{21}{52}×\frac{26}{27}=$
$\frac{15}{19}×\frac{38}{45}=$
$\frac{5}{9}×\frac{3}{10}=$
$\frac{4}{7}×\frac{21}{10}=$
$\frac{3}{14}×\frac{7}{12}=$
$\frac{17}{18}×\frac{9}{5}=$

1.$\frac{20}{9}$ $\frac{16}{27}$ $\frac{5}{3}$ $\frac{80}{7}$
$\frac{15}{2}$ $\frac{3}{14}$ $\frac{10}{9}$ $\frac{1}{2}$
$\frac{2}{27}$ $\frac{1}{4}$ $\frac{1}{2}$ $\frac{2}{9}$
$\frac{1}{14}$ $\frac{3}{11}$ $\frac{7}{18}$ $\frac{2}{3}$
$\frac{1}{6}$ $\frac{6}{5}$ $\frac{1}{8}$ $\frac{17}{10}$

2.计算下面各题,能简算的要简算。(每题3★)
$7 - \frac{4}{9} - \frac{5}{9}$
$\frac{8}{13} + \frac{1}{11} + \frac{5}{13}$
$\frac{5}{6} + \frac{1}{8} - \frac{5}{6} + \frac{7}{8}$
$\frac{8}{15} + \frac{3}{7} - \frac{8}{15}$
$\frac{7}{10} - (\frac{9}{20} + \frac{1}{10})$
$\frac{13}{7} + (\frac{3}{4} + \frac{1}{7}) + \frac{1}{4}$

2.6 $1\frac{1}{11}$ 1
$\frac{3}{7}$ $\frac{3}{20}$ 3

识别出错

3.$x=\frac{1}{5}$ $x=\frac{3}{40}$ $x=1\frac{13}{30}$