19．直接写得数
0 156357 156365 156371 156375 156381 156383 156387 156393 156395 156401 156407 156411 156413 156417 156423 156425 156431 156435 156437 156441 156443 156447 156449 156451 156452 156453 156455 156456 156457 156459 156461 156465 156467 156471 156473 156477 156483 156485 156491 156495 156497 156501 156507 156513 156515 156521 156525 156527 156533 156537 156543 156551 199269
| 1-0.25= | 3.4+1.6= | 3.3-0.8= |
| 15×0.2= | 0.8×0.3= | 0.25×4= |