4．口算：
0 158368 158376 158382 158386 158392 158394 158398 158404 158406 158412 158418 158422 158424 158428 158434 158436 158442 158446 158448 158452 158454 158458 158460 158462 158463 158464 158466 158467 158468 158470 158472 158476 158478 158482 158484 158488 158494 158496 158502 158506 158508 158512 158518 158524 158526 158532 158536 158538 158544 158548 158554 158562 199269
| 2.4÷0.2= | 0.36÷3.6= | 1÷0.01= | 0.63÷0.01= | 360×0.1= |
| 0.56÷0.07= | 0.78÷0.13= | 1÷0.25= | 0.36×0.7+0.64×0.3= | 6.3÷0.25÷4= |