15-(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%)】
网友回答
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.
解析分析: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