0.9+19.9+299.9+3999.9+49999.9怎么巧算?

问题描述:

0.9+19.9+299.9+3999.9+49999.9怎么巧算?

0.9+19.9+299.9+3999.9+49999.9
=1+20+300+4000+50000-0.1*5
=54321-0.5
=54320.5