1.9+39.9+19.9+199.9+0.4巧算求答!快!

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1.9+39.9+19.9+199.9+0.4巧算求答!快!1.9+39.9+19.9+199.9+0.4巧算求答!快!1.9+39.9+19.9+199.9+0.4巧算求答!快!1.9+39.9+1

1.9+39.9+19.9+199.9+0.4巧算求答!快!
1.9+39.9+19.9+199.9+0.4巧算求答!
快!

1.9+39.9+19.9+199.9+0.4巧算求答!快!
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

1.9+39.9+199.9+1999.9+0.4=(2-0.1)+(40-0.1)+(200-0.1)+(2000-0.1)+0.4=2+40+200+2000=2242