| 口算 5×0.9= | 0.42÷7= | 0.4÷8= | 3.9×0= |
| 86÷0.1= | 30×0.05= | 20+12.3= | 54÷0.9= |
| 6.3÷0.7= | 9.54+0.46= | 10-0.1= | 1.5-0.01= |
| 0.8×6= | 3.8×0.5= | 45÷0.45= | 1.3+0.7= |
 + = |  + = | 1- = |  - = |
| 解：5×0.9=4.5 | 0.42÷7=0.06 | 0.4÷8=0.05 | 3.9×0=0 |
| 86÷0.1=860 | 30×0.05=1.5 | 20+12.3=32.3 | 54÷0.9=60 |
| 6.3÷0.7=9 | 9.54+0.46=10 | 10-0.1=9.9 | 1.5-0.01=1.49 |
| 0.8×6=4.8 | 3.8×0.5=1.9 | 45÷0.45=100 | 1.3+0.7=2 |
+= | += | 1-= | -= |
分析：根据小数加减乘除四则运算和分数加减法的计算方法进行计算．据此解答．
点评：本题综合考查了学生基本的计算能力，注意要认真细心．