有理数的加减法1.(-7/2)+(+6/7)+(0.5)+(+8/7) 2.4.5+(-2.5)+28/3+(-47/3)+7/3
问题描述:
有理数的加减法1.(-7/2)+(+6/7)+(0.5)+(+8/7) 2.4.5+(-2.5)+28/3+(-47/3)+7/3
还有,3.(-5.5)-(-3.2)-(-2.5)-(-4.8) 4.(-4)+8/3+(-1/2)+(-8/3) 5.7/2+(-5/6)-(-1/3)-(+0.8)
答
1.(-7/2)+(+6/7)+(0.5)+(+8/7)
=-7/2+1/2+6/7+8/7
=-6/2+14/7
=-3+2
=-1
2.4.5+(-2.5)+28/3+(-47/3)+7/3
=2+(28-47+7)/3
=2+(-12)/3
=2-4
=-2