17.计算下面各题,能简算的要简算.
| 3.2×25×12.5 | $18×\frac{5}{6}÷({\frac{1}{4}×12})$ | 7.2×85%+2.8×0.85 |
| 45×102 | 25.7-(5.7+2.64) | $({\frac{12}{17}-\frac{8}{13}})×\frac{1}{4}+\frac{14}{17}$ |
15.一条彩带用去$\frac{2}{5}$,还剩$\frac{1}{2}$米,用去的彩带与还剩的比较( )
| A. | 用去的多 | B. | 还剩的多 | C. | 一样多 | D. | 无法确定 |
9.从A地到B地,甲车用了6小时,乙车用了5小时,乙车与甲车的速度最简整数比是( )
0 156197 156205 156211 156215 156221 156223 156227 156233 156235 156241 156247 156251 156253 156257 156263 156265 156271 156275 156277 156281 156283 156287 156289 156291 156292 156293 156295 156296 156297 156299 156301 156305 156307 156311 156313 156317 156323 156325 156331 156335 156337 156341 156347 156353 156355 156361 156365 156367 156373 156377 156383 156391 199269
| A. | $\frac{1}{6}$:$\frac{1}{5}$ | B. | $\frac{1}{5}$:$\frac{1}{6}$ | C. | 6:5 | D. | 5:6 |