跪求啦，数学题啊

（125×99+125）×16
= 125×(99+1)×16
=125×100×16
=200000
5×999+599×7+7+3×9+3+9
=5×999+7×(599+1)+3×(9+1)+9
=5×(999+1)+7×600+3×10+4
=5000+4200+30+4
=9234

（125×99+125）×16
=125×99×16+125×16
=125×8×2×99+125×8×2
=1000×2×99+1000×2
=2000×99+2000
=2000×(1+99)
=2000×100
=200000

5×999+599×7+7+3×9+3+9
=5×1000-5+(599+1)×7+(9+1)×3+9
=5000-5+600×7+10×3+9
=5000+4200+30+9-5
=9234

125*(99+1)*16
=125*16*100
=2000*100
=200000

5000-5+7*(599+1)+3*(9+1)+9
=5000+4200+30+9-5
=9234

125*（99+1）*16
＝125*100*8*2
＝125*8*2*100
＝1000*200
＝200000
5*1000+(599+1）*7+3*（9+1）+9-5
＝5000+600*7+3*10+4
＝5000+4200+30+4
9234

(125×99+125）×16
=(12375+125)*16
=12500*16
=200000

5×999+599×7+7+3×9+3+9
=4995+4193+7+27+12
=9234

(125*99+125)*16
=125*(99+1)*8*2
=125*8*2*100