腦算乘法第75講

史豐收速算法,，本個加后進(jìn),，只記個的一位乘多位

    47530275×2=95060550,。   473867×3=1421601,。    24657×4=98628,。 

 本個84060440                 219481                 86408 

后進(jìn)01100011                 121222                 01222

 得積95060550                1421601 只記個            98628

按常規(guī)算法，斜看     

 個位 84060440                 219481                 86408

十位 01100011                 120212                 01222

 得積 95060550                1421601                 98628

    673284×5=3366420                      479237×6=2875422      

055000                                 424282

   331142                                 245124

   3366420                                2875422

379263×7=2654841,。     462347×8=3698776,。       874632×9=7871688。

 193421                  286426                   236478

256142                  341235                   764521

2654841                 3698776                  7871688

習(xí)題：親自練一練

      5843×2=11686         680332×3=2040996      75308×4=301232

              10347×5=51735         332668×6=1996008     

    428657×7=3000599       124625×8=997000      444726×9=4002534