一、口算。
$42÷3=$
$41×5=$
$36+49=$
$70×5=$
$42×6=$
$66÷6=$
$50×50=$
$810+90=$
$880÷4=$
$648÷6=$
$52×20=$
$222×4=$
$41×30=$
$364÷2=$
$27×30=$
$410-90=$
$900÷6=$
$60×17=$
$\frac {1}{5}+\frac {1}{5}=$
$\frac {5}{8}-\frac {2}{8}=$
$\frac {4}{8}+\frac {3}{8}=$
$\frac {8}{9}-\frac {6}{9}=$
$\frac {7}{8}-\frac {4}{8}=$
$\frac {2}{7}+\frac {2}{7}=$
$\frac {2}{5}+\frac {1}{5}=$
$\frac {9}{10}-\frac {6}{10}=$
$\frac {8}{10}-\frac {5}{10}=$
$\frac {2}{4}+\frac {1}{4}=$
$\frac {1}{6}+\frac {4}{6}=$
$\frac {1}{7}+\frac {4}{7}=$

一、14 205 85
350 252 11
2500 900 220
108 1040 888
1230 182 810
320 150 1020
$\frac{2}{5}$ $\frac{3}{8}$ $\frac{7}{8}$
$\frac{2}{9}$ $\frac{3}{8}$ $\frac{4}{7}$
$\frac{3}{5}$ $\frac{3}{10}$ $\frac{3}{10}$
$\frac{3}{4}$ $\frac{5}{6}$ $\frac{5}{7}$

二、在$◯$里填“＞”“＜”或“=”。
$\frac {5}{8}-\frac {4}{8}◯ \frac {3}{4}-\frac {2}{4}$
$\frac {6}{7}◯ \frac {3}{7}+\frac {3}{7}$
$\frac {2}{8}◯ \frac {7}{8}-\frac {5}{8}$
$\frac {1}{3}+\frac {1}{3}◯ \frac {2}{3}$
$\frac {7}{9}◯ \frac {5}{9}+\frac {3}{9}$
$\frac {5}{7}-\frac {3}{7}◯ \frac {7}{7}-\frac {5}{7}$
$\frac {4}{5}-\frac {2}{5}◯ \frac {1}{5}$
$\frac {1}{7}◯ \frac {2}{5}-\frac {1}{5}$
$\frac {5}{9}-\frac {4}{9}◯ \frac {5}{7}-\frac {4}{7}$

二、＜ = =
= ＜ =
＞ ＜ ＜