1.12+(-1)+(-7)-(-3)
2.(-0.5)-(-3.75)+(+2.75)-(+7.5)
3.(-5.3)+(-3.2)-(-2.5)-(+4.8)
4.-23+(-40)-(+31)-(-15)-(-18)
5.40+40+60-70+(-15)-20+(-10)
6.13+(-1.25)-25+(-2.75-5)
7.132+(-12.5)-10.5+127-87+136.5
8.(-18)+12+(-15)+3-(-6)+18
9.15+(-2.5)-1+10-3+(-2)
12-(-4)-3.5
10.1/2-(-2/3)+(-5)-4
11.-2-(-1/2)-5+(1/4)
12.-78-23+127+52-34+12
13.871-87.21+56/19/21-12.79+43/2/21
14.-1/4+5/6+2/3-1/2
15.4.7-(-8.9)-7.5+(-6)
剩下的你就自己编吧!!!!!!
.12+(-1)+(-7)-(-3)
2.(-0.5)-(-3.75)+(+2.75)-(+7.5)
3.(-5.3)+(-3.2)-(-2.5)-(+4.8)
4.-23+(-40)-(+31)-(-15)-(-18)
5.40+40+60-70+(-15)-20+(-10)
6.13+(-1.25)-25+(-2.75-5)
7.132+(-12.5)-10.5+127-87+136.5
8.(-18)+12+(-15)+3-(-6)+18
9.15+(-2.5)-1+10-3+(-2)
12-(-4)-3.5
10.1/2-(-2/3)+(-5)-4
11.-2-(-1/2)-5+(1/4)
12.-78-23+127+52-34+12
13.871-87.21+56/19/21-12.79+43/2/21
14.-1/4+5/6+2/3-1/2
15.4.7-(-8.9)-7.5+(-6)
(-3)+1/2+4/5+(-1/2)+(-1/3)
什么意思?
-3+1/2+4/5-1/2-1/3
=-3+0.4
=-(3-0.4)
=-2.6
(-3)+1/2+4/5+(-1/2)+(-1/3)