一、口算。
$\frac {5}{6}×12=$
$\frac {3}{7}×14=$
$\frac {1}{5}×40=$
$\frac {2}{5}×2=$
$3×\frac {2}{7}=$
$\frac {5}{9}×6=$
$\frac {3}{17}×5=$
$\frac {2}{51}×17=$
$\frac {9}{32}×3=$
$7×\frac {23}{91}=$
$5×\frac {5}{32}=$
$\frac {13}{100}×20=$
$\frac {7}{12}×4=$
$\frac {67}{81}×9=$
$100×\frac {6}{25}=$
$\frac {3}{10}×5=$
$\frac {5}{6}×8=$
$\frac {2}{5}×12=$
$\frac {19}{24}×3=$
$\frac {17}{18}×54=$
$66×\frac {3}{22}=$
$\frac {10}{39}×13=$
$\frac {1}{48}×6=$
$\frac {16}{39}×26=$

10 6 8 $\frac{4}{5}$ $\frac{6}{7}$ $\frac{10}{3}$ $\frac{15}{17}$ $\frac{2}{3}$ $\frac{27}{32}$ $\frac{23}{13}$ $\frac{25}{32}$ $\frac{13}{5}$ $\frac{7}{3}$ $\frac{67}{9}$ 24 $\frac{3}{2}$ $\frac{20}{3}$ $\frac{24}{5}$ $\frac{19}{8}$ 51 9 $\frac{10}{3}$ $\frac{1}{8}$ $\frac{32}{3}$

$\frac{5}{6}×12 = 10$
$\frac{3}{7}×14 = 6$
$\frac{1}{5}×40 = 8$
$\frac{2}{5}×2 = \frac{4}{5}$
$3×\frac{2}{7} = \frac{6}{7}$
$\frac{5}{9}×6 = \frac{10}{3}$
$\frac{3}{17}×5 = \frac{15}{17}$
$\frac{2}{51}×17 = \frac{2}{3}$
$\frac{9}{32}×3 = \frac{27}{32}$
$7×\frac{23}{91} = \frac{23}{13}$
$5×\frac{5}{32} = \frac{25}{32}$
$\frac{13}{100}×20 = \frac{13}{5}$
$\frac{7}{12}×4 = \frac{7}{3}$
$\frac{67}{81}×9 = \frac{67}{9}$
$100×\frac{6}{25} = 24$
$\frac{3}{10}×5 = \frac{3}{2}$
$\frac{5}{6}×8 = \frac{20}{3}$
$\frac{2}{5}×12 = \frac{24}{5}$
$\frac{19}{24}×3 = \frac{19}{8}$
$\frac{17}{18}×54 = 51$
$66×\frac{3}{22} = 9$
$\frac{10}{39}×13 = \frac{10}{3}$
$\frac{1}{48}×6 = \frac{1}{8}$
$\frac{16}{39}×26 = \frac{32}{3}$

二、在$◯$里填“＞”“＜”或“=”。
$\frac {1}{6}×10◯ \frac {1}{6}$
$\frac {3}{4}×1◯ \frac {3}{4}$
$10×\frac {4}{5}◯ \frac {3}{4}×8$
$\frac {7}{13}×0◯ \frac {7}{13}$
$9×\frac {2}{3}◯ \frac {2}{3}×9$
$0×\frac {7}{9}◯ 999×0$
$\frac {3}{4}×4◯ \frac {3}{4}$
$\frac {2}{3}×11◯ \frac {3}{4}×11$
$\frac {7}{8}×6◯ \frac {7}{8}×4$

＞ = ＞ ＜ = = ＞ ＜ ＞

$\frac{1}{6}×10＞\frac{1}{6}$
$\frac{3}{4}×1=\frac{3}{4}$
$10×\frac{4}{5}=8$，$\frac{3}{4}×8=6$，$8＞6$，所以$10×\frac{4}{5}＞\frac{3}{4}×8$
$\frac{7}{13}×0=0＜\frac{7}{13}$
$9×\frac{2}{3}=\frac{2}{3}×9$
$0×\frac{7}{9}=0$，$999×0=0$，所以$0×\frac{7}{9}=999×0$
$\frac{3}{4}×4=3＞\frac{3}{4}$
因为$\frac{2}{3}＜\frac{3}{4}$，所以$\frac{2}{3}×11＜\frac{3}{4}×11$
因为$6＞4$，所以$\frac{7}{8}×6＞\frac{7}{8}×4$