1.18又3/4+(-2.75)+6.125+(-2又5/7)+(-5又1/8)=?2.若|x+6|与|2y-3|互为相反数,求:x+y3.(-4又7/8)-(-5又1/2)+(-4又1/4)-3又1/8=(要过程)4.(-0.5)-(-3又1/4)+2.75-7又1/2=(要过程)

问题描述:

1.18又3/4+(-2.75)+6.125+(-2又5/7)+(-5又1/8)=?
2.若|x+6|与|2y-3|互为相反数,求:x+y
3.(-4又7/8)-(-5又1/2)+(-4又1/4)-3又1/8=(要过程)
4.(-0.5)-(-3又1/4)+2.75-7又1/2=(要过程)

1、18又3/4+(-2.75)+6.125+(-2又5/7)+(-5又1/8)
=(18-2+6-2-5)+(3/4-3/4+1/8-5/7-1/8)
=15-5/7
=14又5/7
2、x+6=0 ==>x=-6
2y-3=0 ==>y=3/2
x+y=-6+3/2=-4.5
3、(-4又7/8)-(-5又1/2)+(-4又1/4)-3又1/8
=(-4+5-4-3)+(-7/8+1/2-1/4-1/8)
=-6+(-1+1/4)
=-6又3/4
4、(-0.5)-(-3又1/4)+2.75-7又1/2
=-1/2-7又1/2+3又1/4+2又3/4
=-8+6
=-2