习题2.6第1题答案
(1)-9
(2)11
(3)-24
(4)47
(5)0
(6)-43
(7)-35
(8)-7
习题2.6第2题答案
(1)0.6
(2)10.2
(3)-7
(4)-6
习题2.6第3题答案
解:(1)原式=[(+14)+(+26)]+[-4)+(-2)+(-3)]
=(+40)+(-9)=31;
(2)原式=(-83)+[(-41)+(+26)+(+15)]
=(-83)+0=-83;
(3)原式=[(-1.8)+(-0.2)]+(+0.7)+1.3]+(-0.9)
=(-2)+2+(-0.9)=-0.9;
(4)原式=【1/4+[+4(3/4)]】+【[-3(1/3)]+[(-6(2/3)]】
=5+(-10)=-5.
习题2.6第4题答案
解:(1)(+1.2)+|-3.1|=1.2+3.1=4.3.
(2)-[4(2/3)+(-1/3)]=-4(1/3).
习题2.6第5题答案
解:(1)(+3500)+(+1500)+(-300)+(-650)+(+600)+(-1800)+(-250)+(-200)=2400(千克).
(2)(+18)+(-9)+(+7)+(-14)+(-6)+(+13)+(-6)+(-8)=-5(千米),即B地在A地南边5千米处.
(18+9+7+14+6+13+6+8)a=81a(升).