1．直接写出得数．
0 162563 162571 162577 162581 162587 162589 162593 162599 162601 162607 162613 162617 162619 162623 162629 162631 162637 162641 162643 162647 162649 162653 162655 162657 162658 162659 162661 162662 162663 162665 162667 162671 162673 162677 162679 162683 162689 162691 162697 162701 162703 162707 162713 162719 162721 162727 162731 162733 162739 162743 162749 162757 199269
| 21×39= | 15×40= | 30×6= | 25×4= |
| 5.8-1.6= | 24+3.2= | 1.6-0.8= | $\frac{1}{2}$+$\frac{1}{2}$= |
| $\frac{6}{7}$-$\frac{4}{7}$= | $\frac{1}{9}$+$\frac{4}{9}$= | $\frac{1}{5}$+$\frac{3}{5}$= | 1-$\frac{1}{3}$= |
