第2个回答 2012-06-02
372×101
=372×(100+1)
=372×100+372
=37200+372
=37572
38×99
=38×(100-1)
=38×100-38
=3800-38
=3762
265-(127+65)
=265-65-127
=200-127
=73
25×64
=25×4×16
=100×16
=1600
178×17+83×178
=178×(17+83)
=178×100
=17800
42×106
=42×(100+6)
=42×100+42×6
=4200+252
=4452
125×7+125
125×(7+1)
=125×8
=1000
125×4×25×8
=(125×8)×(25×4)
=1000×100
=100000