题目内容
计算:
①(-7
)-(4
)+(+1
)-(+2
)-(-3
)
②-
-[
-(1
+
-2)-
]
③(-2
)÷
×(-0.2)÷1.4×(-
)
④(-13
) ×
+(-5
) ×
+(-196
)÷5-(+76
) ÷(-5)
⑤-22×
+(
+
-
) ÷(-
)
⑥-32×(-2)2÷(0.3)2× (-22)+(
) 2-
⑦
-[-32-(-2-3)2÷(-1-
)×2]
⑧|
-
|-|
-
|+|
-
|
①(-7
1 |
5 |
2 |
3 |
1 |
9 |
4 |
5 |
2 |
9 |
②-
2 |
3 |
3 |
4 |
1 |
2 |
3 |
4 |
2 |
3 |
③(-2
1 |
2 |
3 |
4 |
3 |
5 |
④(-13
1 |
3 |
1 |
5 |
2 |
3 |
1 |
5 |
1 |
7 |
1 |
7 |
⑤-22×
1 |
(-4)2 |
1 |
3 |
2 |
7 |
1 |
6 |
1 |
42 |
⑥-32×(-2)2÷(0.3)2× (-22)+(
1 |
3 |
1 |
22 |
⑦
1 |
0.12 |
2 |
3 |
⑧|
3 |
4 |
2 |
3 |
2 |
3 |
4 |
5 |
1 |
4 |
4 |
5 |
分析:(1)先去括号,再把同分母的相加,再从左向右计算即可;
(2)先去括号,再把互为相反数的数相加,再从左向右计算即可;
(3)化小数为分数,把除法转化成乘法,约分即可;
(4)利用乘法分配律计算;
(5)先乘方,再算乘除,最后算加减,有括号的先算括号里的;
(6)先算乘方,再算乘除,最后算加减;
(7)先算乘方,再算乘除,最后算加减,有括号的先算括号里的;
(8)根据绝对值的定义,结合|a-b|=|b-a|进行计算即可.
(2)先去括号,再把互为相反数的数相加,再从左向右计算即可;
(3)化小数为分数,把除法转化成乘法,约分即可;
(4)利用乘法分配律计算;
(5)先乘方,再算乘除,最后算加减,有括号的先算括号里的;
(6)先算乘方,再算乘除,最后算加减;
(7)先算乘方,再算乘除,最后算加减,有括号的先算括号里的;
(8)根据绝对值的定义,结合|a-b|=|b-a|进行计算即可.
解答:解:(1)原式=-7
-2
-4
+1
+3
=-10-
=-10
;
(2)原式=-
-
+1
+
-2+
=-
;
(3)原式=-
×
×
×
×
=-
;
(4)原式=(-13
-5
)×
+(-196
+76
)×
=-
;
(5)原式=-4×
-
×42-
×42+
×42=-19
;
(6)原式=-9×4×
×(-4)+
-
=1600+
-
=1599
;
(7)原式=100-[-9-25×(-
)×2]=100-21=79;
(8)原式=
-
-
+
+
-
=
.
1 |
5 |
4 |
5 |
2 |
3 |
1 |
9 |
2 |
9 |
1 |
3 |
1 |
3 |
(2)原式=-
2 |
3 |
3 |
4 |
1 |
2 |
3 |
4 |
2 |
3 |
1 |
2 |
(3)原式=-
5 |
2 |
4 |
3 |
1 |
5 |
5 |
7 |
3 |
5 |
2 |
7 |
(4)原式=(-13
1 |
3 |
2 |
3 |
1 |
5 |
1 |
7 |
1 |
7 |
1 |
5 |
139 |
5 |
(5)原式=-4×
1 |
16 |
1 |
3 |
2 |
7 |
1 |
6 |
1 |
4 |
(6)原式=-9×4×
100 |
9 |
1 |
9 |
1 |
4 |
1 |
9 |
1 |
4 |
31 |
36 |
(7)原式=100-[-9-25×(-
3 |
5 |
(8)原式=
3 |
4 |
2 |
3 |
4 |
5 |
2 |
3 |
4 |
5 |
1 |
4 |
1 |
2 |
点评:本题考查了有理数的混合运算,解题的关键是注意运算顺序.
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