有理数减法计算题.(要有计算过程,能简便的最好就简便)

问题描述:

有理数减法计算题.(要有计算过程,能简便的最好就简便)
(1):
-5-(-7)-3-5
(2):
(-36)-(-25)-(+36)
(3):
(-8分之1)-(-8分之3)-1又8分之5-8分之7

(1):
-5-(-7)-3-5
=-5+7-3-5
=2-3-5
=-1-5
=-6
(2):
(-36)-(-25)-(+36)
=-36+25-36
=-11-36
=-47
(3):
(-1/8)-(-3/8)-(1+5/8)-7/8
=-1/8+3/8-1-5/8-7/8
=-(1/8+7/8)-1-(-3/8+5/8)
=-1-1-1/4
=-(2+1/4)
=-2又1/4