如题所述
第1个回答 2016-07-22
401×31
=(400+1)×31
=400×31+1×31
=12400+31
=12431
78×201-78
=78×201-78×1
=78×(201-1)
=78×200
=15600
35×301
=35×(300+1)
=35×300+35×1
=10500+35
=10535
=(400+1)×31
=400×31+1×31
=12400+31
=12431
78×201-78
=78×201-78×1
=78×(201-1)
=78×200
=15600
35×301
=35×(300+1)
=35×300+35×1
=10500+35
=10535
第2个回答 2016-07-22
401×31
=400×31+1×31
=12400+31
=12431
78×201
=78×1+78×200
=78+15600
=15678
35×301
=35×300+35×1
=10500+35
=10535本回答被网友采纳
=400×31+1×31
=12400+31
=12431
78×201
=78×1+78×200
=78+15600
=15678
35×301
=35×300+35×1
=10500+35
=10535本回答被网友采纳
第3个回答 2016-07-22
401*31=400*31+31=12400+31=12431
78*201-78=78*(201-1)=78*200=15600
35*301=35*300+35=10500+35=10535
78*201-78=78*(201-1)=78*200=15600
35*301=35*300+35=10500+35=10535