6.下面4个算式结果最大的是( )
| A. | 666×(1+$\frac{2}{5}$) | B. | 666×(1-$\frac{2}{5}$) | C. | 666÷(1-$\frac{2}{5}$) | D. | 666÷(1+$\frac{2}{5}$) |
19.口算
0 137198 137206 137212 137216 137222 137224 137228 137234 137236 137242 137248 137252 137254 137258 137264 137266 137272 137276 137278 137282 137284 137288 137290 137292 137293 137294 137296 137297 137298 137300 137302 137306 137308 137312 137314 137318 137324 137326 137332 137336 137338 137342 137348 137354 137356 137362 137366 137368 137374 137378 137384 137392 199269
| 1÷0.25= | 0.78÷6= | 2.4÷24= |
| 6.6÷0.6= | 5÷0.5= | 34÷0.2= |
| 0.8×7= | 8×0.6= | 70×0.12= |