(125x99+125)x16 =(125x99+125x1)x16 =[125x(99+1)]x16 =(125x100)x16 =125x8x2x100 =1000x200 =200000
（125X99十125)X16 =125X（99十1）X16 =125X100X16 =（125X8）X（100X2） =1000X200 =200000
简便计算(125x99十125)x16 =125x8x2x（99+1） =2000x100 =200000
125×(99+1)
=125×(100-1) =125Ⅹ100-125×1 =12500-125 =12475
第一道题 (125X99+125)X16 =125X(99+1)X16 =25X5X4X4X100 =100X20X100 =200000 第二道题 5X999+5+99X7+7+3X9+3+9 =5X(999+1)+7X(99+1)+3X(9+1)+9 =5000+700+30+9 =5739
你好！简便算法是： (125X99+125)X16 =[125X(99+1))]X16 =[125X100]X16 =12500X16 =200000
(129x99+125)x16 =(129*100-4)*16 =12900*16-64 =12900*(10+6)-64 =129000+77400-64 =206336
125X24=125*(8*3)=(125*8)*3=3000或者进一步125X24=5*5*5*2*2*2*3=(5*2)*(5*2)*(5*2)*3=3000（125X99+125)\25=(25*5*99+25*5)/25=5*99+5=5*(99+1)=500