-(5
+3
)-4
1
×43×70%-2÷
【2.1+7÷(3
-1
)】×1
(
×5÷
×5)×(1.685÷1
-0.235×
)1-【4
-(31%-
)×16
】÷1
15
÷63%-【24
-8
×(3
-287.5%)】解:(1)15
-(5
+3
)-4
=15
-5
-3
-4
,=15
-3
-(5
+4
),=11
-10,=1
;(2)1
×43×70%-2÷
=53.75×70%-2÷
,=37.625-2.5,
=35.125;
(3)[2.1+7÷(3
-1
)]×1
=[2.1+7÷
]×1
,=[2.1+4.8]×1
,=6.9×1
,=11.5;
(4)(
×5÷
×5)×(1.685÷1
-0.235×
)=(
÷
×5)×(1.348-0.188),=25×1.16,
=29;
(5)1-[4
-(31%-
)×16
]÷1
=1-[4
-0.21×16
]÷1
,=1-[4
-3
]÷1
,=1-
÷1
,=1-
,=
;(6)15
÷63%-[24
-8
×(3
-287.5%)]=15
÷63%-[24
-8
×1],=15
÷63%-16,=25-16,
=9.
分析:根据整数、分数、小数、百分数的四则混合运算进行计算即可得到答案.
点评:此题主要考查的是整数、分数、小数、百分数的四则混合运算.