i) 58:252=58:(52)2=58:52.2=58:54=58−4=54
k) 49:642=49:(43)2=49:43.2=49:46=49−6=43
l) 225:324=225:(25)4=225:25.4=225:220=225−20=25
m) 1253:254=(53)3:(52)4=53.3:52.4=59:58=5
e) 38:36=38−6=32
f) 210:83=210:(23)3=210:23.3=210:29=210−9=2
g) 127:67=(12:6)7=27
h_ 215:813kết quả là số dư nên không tính ( đề sai )
a) 410.230=(22)10.230=22.10.230=220.230=220+30=250
b) 925.274.813=(32)25.(33)4.(34)3=33.25.33.4.34.3=375.312.312=375+12+12=399
c) 2550.1255=(52)50.(53)5=52.50.53.5=5100.515=5100+15=5115
d) 643.48.164=(43)3.48.(42)4=43.3.48.42.4=49.48.48=49+8+8=425