14.15-(7-6)-2.125
×+×
(111+999)÷[56×(-)]
6.45×0.75+4.55×75%-
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解:(1)14.15-(7-6)-2.125,
=14.15-7+6-2.125,
=(14.15+6.85)-(7.875+2.125),
=21-10,
=11;
(2)×+×,
=×+×,
=(+)×,
=1×,
=;
(3)(111+999)÷[56×(-)],
=1110÷[56×-56×],
=1110÷(24-21),
=1110÷3,
=370;
(4)6.45×0.75+4.55×75%-,
=6.45×0.75+4.55×0.75-0.75×1,
=(6.45+4.55-1)×0.75,
=10×0.75,
=7.5.
解析分析:(1)先去掉括号,然后运用加法结合律,以及减去的性质简算;
(2)先根据积不变性质,把×变成×,再运用乘法分配律简算;
(3)先算第一个小括号里面的加法,中括号里面的运算运用乘法分配律简算,最后再算括号外的除法;
(4)运用乘法分配律简算.
点评:此题是考查四则混合运算,要仔细观察算式的特点,灵活运用一些定律进行简便计算.