1.直接写出得数。(每题1 ⭐)
$\frac{1}{8}-\frac{1}{9}=$
$\frac{5}{9}-\frac{1}{3}=$
$\frac{5}{8}-\frac{1}{24}=$
$\frac{3}{16}+\frac{9}{16}=$
$\frac{7}{10}-\frac{1}{10}=$
$\frac{3}{5}+\frac{1}{8}=$
$1-\frac{5}{6}=$
$\frac{2}{3}+\frac{1}{6}=$
$1-\frac{8}{13}=$
$\frac{7}{9}-\frac{2}{9}=$
$\frac{4}{5}+\frac{7}{10}=$
$\frac{1}{6}+\frac{1}{4}=$
$\frac{2}{7}-\frac{3}{14}=$
$\frac{1}{3}+\frac{1}{24}=$
$\frac{9}{5}-\frac{3}{5}=$
$\frac{2}{7}-\frac{1}{14}=$
$2+\frac{3}{14}=$
$\frac{3}{4}-\frac{3}{16}=$
$\frac{3}{16}+\frac{5}{48}=$
$\frac{7}{25}-\frac{1}{5}=$

$\frac{1}{72}$ $\frac{2}{9}$ $\frac{7}{12}$ $\frac{3}{4}$
$\frac{3}{5}$ $\frac{29}{40}$ $\frac{1}{6}$ $\frac{5}{6}$
$\frac{5}{13}$ $\frac{5}{9}$ $\frac{3}{2}$ $\frac{5}{12}$
$\frac{1}{14}$ $\frac{3}{8}$ $\frac{6}{5}$ $\frac{3}{14}$
$2\frac{3}{14}$ $\frac{9}{16}$ $\frac{7}{24}$ $\frac{2}{25}$

2.计算下面各题,能简算的要简算。(每题3★)
$\frac{1}{5}+\frac{7}{9}-\frac{1}{5}+\frac{2}{9}$
$0.6+\frac{2}{7}+\frac{1}{3}$
$\frac{9}{10}-(\frac{3}{4}-\frac{1}{5})$
$\frac{8}{15}-(\frac{1}{2}-\frac{7}{15})$
$\frac{34}{33}-\frac{5}{7}-\frac{2}{7}$
$\frac{5}{12}+\frac{11}{15}-\frac{2}{5}+\frac{7}{12}$

1 $\frac{128}{105}$ $\frac{7}{20}$
$\frac{1}{2}$ $\frac{1}{33}$ $1\frac{1}{3}$

识别出错

3.(1)$(16×12+16×10+12×10)×2=944(\mathrm{cm}^2)$
(2)$(20×8+20×3+8×3)×2=488(\mathrm{cm}^2)$
$5×5×4=100(\mathrm{cm}^2)$
$488+100=588(\mathrm{cm}^2)$