(-0.5)+(9/2)+(-19/2)+9.75=?
问题描述：
(-0.5)+(9/2)+(-19/2)+9.75=?
求求各位大侠了,我是新人啊
答
(-0.5)+(9/2)+(-19/2)+9.75
=-0.5+9/2-19/2+9.75
=(9.75-0.5)-(19/2-9/2)
=9.25-5
=4.25