A-A+
计算:(1)(-23)+(-12);(2)6-(3)-(-7)+(-2);(3)-1613+
问题详情
计算:
(1)(-23)+(-12);
(2)6-(3)-(-7)+(-2);
(3)-16
(4)-0.5-(-3
(5)-(-7)+(-2);
(6)(-4
(7)(9)+(-7)+(10)+(-3)+(-9);
(8)1-3+5-7+9-11+…+97-99+100.
参考答案
(1)(-23)+(-12)=-35;
(2)6-(+3)-(-7)+(-2)=6-3+7-2=13-5=8;
(3)-1613+2916=1256;
(4)-0.5-(-314)+2.75-712=-0.5-7.5+3.25+2.75=-8+6=-2;
(5)-(-7)+(-2)=7-2=5;
(6)(-414)-(+513)-(-414)=-414+414-513=-513;
(7)(+9)+(-7)+(+10)+(-3)+(-9)=9-7+10-3-9=0;
(8)1-3+5-7+9-11+…+97-99+100=(1-3)+(5-7)+(9-11)+…+(97-99)+100=-2-2-2-…-2+100=-2×25+100=50.
考点: