Question

5又5分之2+12-6.2+3又5分之3-12-3.8+5又2分之1等于几

Answer 1

5又5分之2+12-6.2+3又5分之3-12-3.8+5又2分之1
=5+2/5+12-6-1/5+3+3/5-12-4+1/5+5+1/2
=2/5+3+3/5+1/2
=4又2分之1

追问

用有理数的减法计算，谢谢，速度啊

追答

5又5分之2+12-6.2+3又5分之3-12-3.8+5又2分之1
=5.4+12-6.2+3.6-12-3.8+5.5
=5.4+3.6+12-12-(6.2+3.8)+5.5
=9-10+5.5
=4.5