当前位置:初中试题 > 数学试题 > 有理数的混合运算 > 计算:(1)-13+514-317-514+1267;(2)3.75-(-12)+(-423)+(-0.5)+(-634);(3)325+(-278)+(-35...
题目
题型:解答题难度:一般来源:不详
计算:
(1)-
1
3
+5
1
4
-3
1
7
-5
1
4
+12
6
7

(2)3.75-(-
1
2
)+(-4
2
3
)+(-0.5)+(-6
3
4
);
(3)3
2
5
+(-2
7
8
)+(-3
5
12
)+5
3
5
+(-1
1
8
)+5
5
12

(4)(-4
5
8
)+(-3.75)+(-2
3
8
)+(-3
1
4
);
(5)(-123)+3
1
3
+(-4
1
4
)+(+123)+(-
1
3
)+(-
3
4
);
(6)25×
3
4
+(-25)×(-
1
4
);
(7)(-3)2÷2
1
4
×(-
2
3
2+4-22×(-
1
3
);
(8)(-79)÷2
1
4
+
4
9
×(-29);
(9)[30-(
7
9
+
5
6
-
11
12
)×36]÷(-5)
(10)(-1)3-(1-
1
2
)÷3×[3-(-3)2]
(11)(
1
4
+
1
12
-
7
18
-
1
36
)÷
1
36
-2×(-
1
3

(12)-22-(1-
1
5
×0.2)÷(-2)3
(13)99
17
18
×(-9)
(14)-36
9
11
÷9
(15)(-7)×(+5)-90÷(-15)
(16)(-
2
3
)×(-18)-(+0.25)×(-6)÷(-5)
答案
(1)-
1
3
+5
1
4
-5
1
4
-3
1
7
+12
6
7

=-
1
3
+9
5
7

=9
8
21


(2)3.75-(-
1
2
)+(-4
2
3
)+(-0.5)+(-6
3
4

=3.75+
1
2
-4
2
3
-0.5-6
3
4

=3.75-6
3
4
+
1
2
-0.5-4
2
3

=-3-4
2
3

=-7
2
3


(3)3
2
5
+(-2
7
8
)+(-3
5
12
)+5
3
5
+(-1
1
8
)+5
5
12

=3
2
5
+5
3
5
+(-2
7
8
)+(-1
1
8
)+(-3
5
12
)+5
5
12

=9-4+2
=7;

(4)(-4
5
8
)+(-3.75)+(-2
3
8
)+(-3
1
4

=(-4
5
8
)+(-2
3
8
)+(-3
1
4
)+(-3.75)
=-7-7
=-14;

(5)(-123)+3
1
3
+(-4
1
4
)+(+123)+(-
1
3
)+(-
3
4

=(-123)+(+123)+3
1
3
+(-
1
3
)+(-4
1
4
)+(-
3
4

=0+3-5
=-2;

(6)25×
3
4
+(-25)×(-
1
4

=25×(
3
4
+
1
4

=25;

(7)(-3)2÷2
1
4
×(-
2
3
2+4-22×(-
1
3
);
=9×
4
9
×
4
9
+4-4×(-
1
3

=
16
9
+4+
4
3

=
64
9


(8)(-79)÷2
1
4
+
4
9
×(-29)
=(-79)×
4
9
+
4
9
×(-29)
=(-79-29)×
4
9

=-108×
4
9

=-48;

(9)[30-(
7
9
+
5
6
-
11
12
)×36]÷(-5)
=[30-(
7
9
×36+
5
6
×36-
11
12
×36)]÷(-5)
=[30-28-30+33]÷(-5)
=5÷(-5)
=-1;

(10)(-1)3-(1-
1
2
)÷3×[3-(-3)2]
=-1-
1
2
×
1
3
×[3-9]
=-1-
1
2
×
1
3
×[3-6]
=-1+1
=0;

(11)(
1
4
+
1
12
-
7
18
-
1
36
)÷
1
36
-2×(-
1
3

=(
1
4
+
1
12
-
7
18
-
1
36
)×36+
2
3

=
1
4
×36+
1
12
×36-
7
18
×36-
1
36
×36+
2
3

=9+3-14-1+
2
3

=-
7
3


(12)-22-(1-
1
5
×0.2)÷(-2)3
=-22-(1-
1
25
)÷(-8)
=-22-
24
25
×(-
1
8

=-22+
3
25

=-21
22
25


(13)99
17
18
×(-9)
=(100-
1
18
)×(-9)
=100×(-9)-
1
18
×(-9)
=-900+
1
2

=-899
1
2


(14)-36
9
11
÷9
=-36×
1
9
-
9
11
×
1
9

=-4
1
11


(15)(-7)×(+5)-90÷(-15)
=-35+6
=-29;

(16)(-
2
3
)×(-18)-(+0.25)×(-6)÷(-5)
=12-(-1.5)÷(-5)
=12-0.3
=11.7.
核心考点
试题【计算:(1)-13+514-317-514+1267;(2)3.75-(-12)+(-423)+(-0.5)+(-634);(3)325+(-278)+(-35】;主要考察你对有理数的混合运算等知识点的理解。[详细]
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