29 * 72 = 2088
29x72=72x(30一1)=72x30一72=2160-72=2088
7 2 - 2 9= - 4 3
289 * 72 578202 320808
208乘72竖式计算208*72=14976
72*29+72=72*(29+1)=72*30=2160
原式=(92+1)x72+92x28-9x92=92x72+1x72+92x28-9x92=92x72+92x28+72-9x92=92x(72+28)+72-828=92x100+72-828=9200+72-828=8444
85*53=450529*72=208890*15=135036*44=1584
. 72X 30一一2160