45.9×12.4-4.1×3×45.9请问这道题怎么巧算?
问题描述：
45.9×12.4-4.1×3×45.9请问这道题怎么巧算?
答
45.9×12.4-4.1×3×45.9
=45.9*(12.4-4.1*3)
=45.9*0.1
=4.59还有一个45.9呢