一、口算。
7.12 + 1.8 =
272 + 172 =
24 ÷ 0.12 =
60.8 - 40.9 =
1.1 × 0.09 =
0.88 ÷ 4.4 =
2.3 × 0.7 =
8.19 ÷ 0.3 =
2.4 × 5 =
1480 ÷ 4 =
12.19 - 2.91 =
0.26 + 0.78 =
$\frac{1}{3} × 7.5 =$
$\frac{10}{7} ÷ \frac{5}{7} =$
$\frac{6}{7} + \frac{5}{21} =$
$\frac{7}{10} × \frac{5}{14} =$
$\frac{9}{25} ÷ 12 =$
$\frac{11}{25} × \frac{10}{33} =$
$\frac{3}{5} × \frac{5}{6} =$
$\frac{4}{5} - 0.75 =$
$30 × \frac{7}{60} =$
$\frac{1}{6} ÷ \frac{1}{30} =$
$\frac{2}{3} × 9 =$
$\frac{7}{12} ÷ \frac{7}{8} =$

1. 8.92
2. 444
3. 200
4. 19.9
5. 0.099
6. 0.2
7. 1.61
8. 27.3
9. 12
10. 370
11. 9.28
12. 1.04
13. $\frac{5}{2}$
14. 2
15. $\frac{23}{21}$
16. $\frac{1}{4}$
17. $\frac{3}{100}$
18. $\frac{2}{15}$
19. $\frac{1}{2}$
20. $\frac{1}{20}$
21. $\frac{7}{2}$
22. 5
23. 6
24. $\frac{2}{3}$

二、计算下面各题，能简算的要简算。
$7÷\dfrac{7}{6}-\dfrac{7}{6}÷7$
$\dfrac{2}{7}+\dfrac{3}{8}×\dfrac{4}{9}+\dfrac{1}{2}$
$0.4×\dfrac{7}{9}+\dfrac{2}{9}×\dfrac{2}{5}$
$(3.8-7.7÷2.5)×2$
$30.6+9.6÷3.2-14.82$
$3.5×11+8×3.5+3.5$

1. $5\dfrac{5}{6}$
2. $\dfrac{20}{21}$
3. $\dfrac{2}{5}$
4. 1.44
5. 18.78
6. 70