Question

42.3x9.9x0.423的简便方法？

Answer 1

12.3×9.9再×0.423的简便算法，是都变成0.4 23×100再乘上0.42 13，嗯。9.9变成10.10-0.1，这道题就是0.323×990。

Answer 2

42.3×9.9×0.423
=42.3×3.3×3×0.423
=（42.3×3+42.3×0.3)×0.423
=（126.9+12.69)×0.423
=139.59×0.423
=60.30288