41×101 7.8++2.2+72×(+) 2.5×1.25×32[1-(+)]÷(-)÷(+)
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解:(1)41×101,
=41×100+41×1,
=4100+41,
=4141;
(2)7.8++2.2+,
=(7.8+2.2)+(),
=10+1,
=11;
(3)72×(+),
=72×+72×,
=27+32,
=59;
(4)2.5×1.25×32,
=(2.5×4)×(1.25×8),
=10×10,
=100;
(5)[1-(+)]÷,
=[1-]÷,
=,
=2;
(6)(-)÷(+),
=,
=.
解析分析:(1)(3)运用乘法分配律解答,
(2)运用加法交换律和结合律解答,
(4)化32=4×8,再运用乘法交换律和结合律解答,
(5)(6)依据四则混合运算顺序:先算第二级运算,再算第一级运算,如果只含有同一级运算,按照从左到右顺序计算,有括号先算括号里面的顺序解答.
点评:本题考查知识点:(1)正确选择并运用简便算法解决问题,(2)依据四则运算顺序正确进行计算.