16.先估算,再列竖式计算:
0 160539 160547 160553 160557 160563 160565 160569 160575 160577 160583 160589 160593 160595 160599 160605 160607 160613 160617 160619 160623 160625 160629 160631 160633 160634 160635 160637 160638 160639 160641 160643 160647 160649 160653 160655 160659 160665 160667 160673 160677 160679 160683 160689 160695 160697 160703 160707 160709 160715 160719 160725 160733 199269
388×4≈; 6×210≈; 456×7≈; 8×199≈; 304×5≈; 701×3≈; 388×4=; 6×210=; 456×7=; 8×199=; 304×5=; 701×3=; | |||