题目内容
计算:
(1)0.125×(-7)×8;
(2)-
十(0.3×3
+
)÷|-
|;
(3)-9
×(-69);
(4)(-1
-
+
)÷(-
);
(5)[2
-(
-
+
)×36]÷5;
(6)(-370)×(-
)+0.25×24.5+(-5
)×(-25%).
(1)0.125×(-7)×8;
(2)-
| 1 |
| 12 |
| 1 |
| 3 |
| 1 |
| 3 |
| 1 |
| 4 |
(3)-9
| 22 |
| 23 |
(4)(-1
| 1 |
| 2 |
| 3 |
| 8 |
| 7 |
| 12 |
| 1 |
| 24 |
(5)[2
| 1 |
| 2 |
| 7 |
| 9 |
| 11 |
| 12 |
| 1 |
| 6 |
(6)(-370)×(-
| 1 |
| 4 |
| 1 |
| 2 |
分析:(1)根据乘法交换律进行计算即可;
(2)先算括号里面的,再算除法,最后算加减即可;
(3)根据乘法分配律进行计算即可;
(4)根据乘法分配律进行计算即可;
(5)先算小括号里面的,再算中括号里面的,最后算除法;
(6)根据乘法分配律进行计算即可.
(2)先算括号里面的,再算除法,最后算加减即可;
(3)根据乘法分配律进行计算即可;
(4)根据乘法分配律进行计算即可;
(5)先算小括号里面的,再算中括号里面的,最后算除法;
(6)根据乘法分配律进行计算即可.
解答:解:(1)原式=(0.125×8)×(-7)
=1×(-7)
=-7;
(2)原式=-
+(
×
+
)÷
=-
+
×4
=-
+
=
;
(3)原式=(-10+
)×(-69)
=(-10)×(-69)+
×(-69)
=690-3
=687;
(4)原式=(-1
)×(-24)-
×(-24)+
×(-24)
=36+9-14
=31;
(5)原式=[
-(
×36-
×36+
×36)]÷5
=[
-(28-33+6)]÷5
=[
-1]÷5
=
×
=
;
(6)原式=370×
+
×24.5+
×
=
×(370+24.5+
)
=
×400
=100.
=1×(-7)
=-7;
(2)原式=-
| 1 |
| 12 |
| 3 |
| 10 |
| 10 |
| 3 |
| 1 |
| 3 |
| 1 |
| 4 |
=-
| 1 |
| 12 |
| 4 |
| 3 |
=-
| 1 |
| 12 |
| 16 |
| 3 |
=
| 21 |
| 4 |
(3)原式=(-10+
| 1 |
| 23 |
=(-10)×(-69)+
| 1 |
| 23 |
=690-3
=687;
(4)原式=(-1
| 1 |
| 2 |
| 3 |
| 8 |
| 7 |
| 12 |
=36+9-14
=31;
(5)原式=[
| 5 |
| 2 |
| 7 |
| 9 |
| 11 |
| 12 |
| 1 |
| 6 |
=[
| 5 |
| 2 |
=[
| 5 |
| 2 |
=
| 3 |
| 2 |
| 1 |
| 5 |
=
| 3 |
| 10 |
(6)原式=370×
| 1 |
| 4 |
| 1 |
| 4 |
| 11 |
| 2 |
| 1 |
| 4 |
=
| 1 |
| 4 |
| 11 |
| 2 |
=
| 1 |
| 4 |
=100.
点评:本题考查的是有理数的混合运算,在进行有理数的混合运算时,注意各个运算律的运用,使运算过程得到简化.
练习册系列答案
相关题目