计算(-3/2)-(-5/4)-(+7/2)-(21/4)+(9/4)要有计算过程

问题描述:

计算(-3/2)-(-5/4)-(+7/2)-(21/4)+(9/4)
要有计算过程

答案是-27/4

(-3/2)-(-5/4)-(+7/2)-(21/4)+(9/4)
=-3/2+5/4-7/2-21/4+9/4
=(-3/2-7/2)+(5/4-21/4+9/4)
=-5-7/4
=-27/4

(-3/2)-(-5/4)-(+7/2)-(21/4)+(9/4)
=-3/2+5/4-7/2-21/4+9/4
=(-3/2-7/2)+(9/4+5/4-21/4)
=-5-7/4
=-6又3/4