19．列竖式计算．
| 4.6+5.9= | 25×68= | 529÷3= |
| 52×29= | 10-3.8= | 694÷5= |
18．直接写出得数．
0 161022 161030 161036 161040 161046 161048 161052 161058 161060 161066 161072 161076 161078 161082 161088 161090 161096 161100 161102 161106 161108 161112 161114 161116 161117 161118 161120 161121 161122 161124 161126 161130 161132 161136 161138 161142 161148 161150 161156 161160 161162 161166 161172 161178 161180 161186 161190 161192 161198 161202 161208 161216 199269
| 15×200= | 5.6+1.9= | 600÷6= | 20-19.9= |
| 0÷18= | 6.5-5= | 79×31≈ | 588÷4≈ |