解:

+(5+7

×3

)×

,
=

+(5+26)×

,
=

+31×

,
=3

;
(2)1.75×0.24+0.76÷

,
=1.75×0.24+0.76×1.75,
=1.75×(0.24+0.76),
=1.75×1,
=1.75;
(3)2012×20.11-201.2×201,
=201.2×201.1-201.2×201,
=201.2×(201.1-201),
=201.2×0.1,
=20.12;
(4)1-

-

-


,
=1-(

+

+

+

),
=1-

,
=

分析:(1)按则运算的顺序,先算小括号里的乘,再算小括号里的加,然后算括号外面的乘,最后算括号外面的加;
(2)把0.76÷

变成0.76×1.75,利用乘法的分配律变成1.75×(0.24+0.76)计算简便;
(3)把2012×20.11变成201.2×201.1,利用乘法的分配律变,201.2×(201.1-201)计算简便;
(4)把原算是变成1-(

+

+

+

)计算简便.
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.