一、口算。
$1.48 + 0.22 =$
$678 + 295 =$
$752 - 299 =$
$0.125 × 8 =$
$5 × 490 =$
$90 ÷ 0.9 =$
$3.2 × 0.05 =$
$9.6 ÷ 1.2 =$
$628 ÷ 4 =$
$0.44 × 4 =$
$0.28 × 0 =$
$5.4 ÷ 0.2 =$
$8.2 - 0.72 =$
$4.24 - 1.89 =$
$9.6 ÷ 120 =$
$\frac{3}{5} × \frac{1}{3} =$
$\frac{2}{15} - \frac{1}{10} =$
$\frac{2}{3} - 0.4 =$
$\frac{1}{15} ÷ 3 =$
$\frac{7}{12} × \frac{3}{14} =$
$\frac{8}{9} ÷ \frac{9}{8} =$
$1.8 ÷ \frac{3}{5} =$
$\frac{7}{9} ÷ \frac{7}{8} =$
$\frac{13}{5} - \frac{8}{15} =$
$\frac{1}{2} × \frac{1}{11} =$
$\frac{4}{9} × \frac{3}{5} =$
$2.8 × \frac{1}{14} =$
$\frac{3}{10} + \frac{7}{8} =$
$\frac{20}{7} - 2 =$
$\frac{7}{15} ÷ \frac{7}{5} =$

1.7
973
453
1
2450
100
0.16
8
157
1.76
0
27
7.48
2.35
0.08
$\frac{1}{5}$
$\frac{1}{30}$
$\frac{4}{15}$
$\frac{1}{45}$
$\frac{1}{8}$
$\frac{64}{81}$
3
$\frac{8}{9}$
$\frac{31}{15}$
$\frac{1}{22}$
$\frac{4}{15}$
$\frac{1}{5}$
$\frac{47}{40}$
$\frac{6}{7}$
$\frac{1}{3}$

二、填表。
图上距离 实际距离 比例尺
2 cm 40 km
()cm 6：1
2.3 cm ()m 1：30000
()cm 180 km 1：12000000

1:2000000
3
690
1.5