一、口算。
$5.38 + 5.62 =$
$6.31 - 2.01 =$
$7.99 × 100 =$
$623 + 892 =$
$5.5 × 0.6 =$
$0.34 ÷ 0.4 =$
$200 × 0.064 =$
$4.75 - 3.65 =$
$19.9 + 10.01 =$
$48 ÷ 0.04 =$
$5.05 × 40 =$
$7.52 ÷ 2 =$
$\frac{3}{7} ÷ \frac{1}{5} =$
$\frac{3}{10} × \frac{5}{16} =$
$\frac{3}{4} + \frac{7}{8} =$
$\frac{7}{6} - \frac{2}{3} =$
$\frac{2}{5} × \frac{2}{3} =$
$\frac{3}{8} ÷ \frac{5}{4} =$
$\frac{2}{9} × \frac{5}{6} =$
$0.4 - \frac{3}{8} =$
$30 ÷ \frac{6}{5} =$
$\frac{3}{8} ÷ \frac{9}{4} =$
$\frac{3}{4} - \frac{2}{15} =$
$2.4 × \frac{5}{6} =$

1. 11
2. 4.3
3. 799
4. 1515
5. 3.3
6. 0.85
7. 12.8
8. 1.1
9. 29.91
10. 1200
11. 202
12. 3.76
13. $\frac{15}{7}$
14. $\frac{3}{32}$
15. $\frac{13}{8}$
16. $\frac{1}{2}$
17. $\frac{4}{15}$
18. $\frac{3}{10}$
19. $\frac{5}{27}$
20. $\frac{1}{40}$
21. 25
22. $\frac{1}{6}$
23. $\frac{37}{60}$
24. 2

二、计算下面各题，能简算的要简算。
$1 - \frac{5}{8} ÷ ( \frac{1}{2} + \frac{8}{9} )$
$\frac{14}{9} × \frac{11}{10} - \frac{5}{9} × \frac{11}{10}$
$\frac{26}{9} ÷ \frac{14}{15} × \frac{6}{13} ÷ \frac{20}{21}$
$4.44 × 2.5$
$2.7 ÷ 4 + 6.3 × 0.25$
$0.15 × [ 1.4 ÷ (0.7 - 0.65) ]$

1. $\frac{11}{20}$
2. $\frac{11}{10}$
3. $\frac{3}{2}$
4. 11.1
5. 2.25
6. 4.2