18．列竖式计算．
| 183÷5= | 824÷4= | 78×34= |
| 65×59= | 83×41= | 320÷5= |
17．口算．
0 159567 159575 159581 159585 159591 159593 159597 159603 159605 159611 159617 159621 159623 159627 159633 159635 159641 159645 159647 159651 159653 159657 159659 159661 159662 159663 159665 159666 159667 159669 159671 159675 159677 159681 159683 159687 159693 159695 159701 159705 159707 159711 159717 159723 159725 159731 159735 159737 159743 159747 159753 159761 199269
| 120÷6= | 30×10= | 3000÷5= | 80÷2= |
| 12×30= | 2000÷4= | 53×20= | 90×50= |
| 360÷4= | 89×30= | 32×48= | 43×23= |