40×51+51×44
=51×(40+44)
=(50+1)×88
=50×88+88
=4400+88
=4488
40×51+51×44
=51×(44+40)
=51×84
=4284
解: 40X51十51X44
=51X(40十44)
=(50十1)X84
=50X84十1X84
=4200十84
=4284
这个很好算的
40*51+51*44=40*51+51*(40+4)=40*51+51*40+51*4=2040+2040+204=4284
原式=51×(40+44)=4284或=50×84+84