| 23+19= | 640-450= | 96÷3= | 44+49= |
| 80÷8= | 99÷9= | 84÷4= | 85+28= |
| 7.3-3.6= | 7+9.3= | 5-2.7= | 0÷3= |
| 30×50= | 15×20= | 2000÷4= | 84×0= |
| 580-340= | 5.7+9.1= | 800÷4= | 60×30= |
| 3600÷9= | 25×50= | 13×2000= | 72÷4= |
| 3.5+7.2= | 9.8-2.7= | 120×4= | 892×1= |
| 389+101= | 700×7= | 456-120= | 457+17= |
| 7200÷9= | 88÷4= | 44×2= | 75+25= |
| 25×4= | 50×2= | 70×20= | 900÷3= |
| 10-2.9= | 12+7.8= | 560+40= | 17×4= |
×4.2=1
=
×
=4
，分数与小数相乘，一般把小数化成________后再计算．有时也可以这样算：1在横线里填上“＜”或“＞”．
| 2.78×1.02________2.78 | 0.99×0.15________0.15 | 5.2÷0.8________5.2 |
| 7.14÷1.2________7.14 | 2.565656________2.6 | 9.34________9.333… |
．