1.9+39.9+19.9+199.9+0.4巧算求答!
问题描述：
1.9+39.9+19.9+199.9+0.4巧算求答!
快!
答
1.9+39.9+19.9+199.9+(0.1+0.1+0.1+0.1)
=(1.9+0.1)+(39.9+0.1)+(19.9+0.1)+(199.9+0.1)
=2+40+20+200
=262