用递等式计算. (1)1292+540÷18×24(2)1.05×(3.8-0.8)÷6.3(3)÷[×(+)](4)[1-()]÷.
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解:(1)1292+540÷18×24,
=1292+30×24,
=1292+720,
=2012;
(2)1.05×(3.8-0.8)÷6.3,
=1.05×3÷6.3,
=3.15÷6.3,
=0.5;
(3)÷[×(+)],
=÷[×],
=÷,
=;
(4)[1-()]÷,
=[1-]÷,
=÷,
=.
解析分析:(1)先算除法,再算乘法,最后算加法;
(2)先算减法,再算乘法,最后算除法;
(3)先算加法,再算乘法,最后算除法;
(4)先算加法,再算减法;最后算除法.
点评:此题主要考查分数、整数、小数的四则混合运算的运算顺序和应用运算定律进行简便计算.