问题
解答题
计算下列各式: (1)(-13)+(-8) (2)-27-(-17) (3)(-
(4)-1+(-2)-(-3)-5 (5)-24×(-
(6)|-2
(7)(-3)×
(8)
(9)-7×(-
|
答案
(1)(-13)+(-8)=-21;
(2)-27-(-17)=-10;
(3)(-
)×(-5 6
)=3 10
;1 4
(4)-1+(-2)-(-3)-5
=-1-2+3-5
=-8+3
=-5;
(5)-24×(-
+1 2
-3 4
)1 3
=24×
-24×1 2
+24×3 4 1 3
=12-18+8
=2;
(6)|-2
|-(-2.5)+1-|1-21 2
|1 2
=2.5+2.5+1-1.5
=6-1.5
=4.5;
(7)(-3)×
×(-5 6
)×(-4 5
)1 4
=-3×
×5 6
×4 5 1 4
=-
;1 2
(8)
+1 6
+1 20
+1 12 1 30
=
+10 60
+3 60
+5 60 2 60
=
;1 3
(9)-7×(-
)+26×(-22 7
)-2×22 7 22 7
=(7-26-2)×22 7
=-21×22 7
=-66.