×+÷÷[×(-)]×30+2÷201×19.5-19.5+×(÷) 74.6-8.44-1.56.
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解:
(1)×+÷,
=+,
=;
(2)÷[×(-)],
=÷[×],
=÷,
=2;
(3)×30+2÷,
=×30+2×
=×(30+2),
=×32,
=12;
(4)201×19.5-19.5,
=(201-1)×19.5,
=200×19.5,
=3900;
(5)+×(÷),
=+×,
=+,
=;
(6)74.6-8.44-1.56,
=74.6-(8.44+1.56),
=74.6-10,
=64.6.
解析分析:(1)先算乘法和除法,再算加法;
(2)先算减法,再算乘法,最后算除法;
(3)根据乘法分配律进行计算;
(4)根据乘法分配律进行计算;
(5)先算除法,再算乘法,最后算加法;
(6)根据连减的性质进行计算.
点评:考查了运算定律与简便运算,四则混合运算.注意运算顺序和运算法则,灵活运用所学的运算律简便计算.