(1)0.75×99
(2)0.125×32×0.25
(3)

(4)2.5+2.8+2.2+6.5.解:(1)0.75×99,
=0.75×(100-1),
=0.75×100-0.75,
=75-0.75,
=74.25;
(2)0.125×32×0.25,
=(0.125×8)×(4×0.25),
=1×1,
=1;
(3)
,=
,=
(
),=
1,=
;(4)2.5+2.8+2.2+6.5,
=(2.5+6.5)+(2.8+2.2),
=9+5,
=14.
分析:(1)0.75×99,运用乘法分配律进行简算;
(2)0.125×32×0.25,把32 分解为8×4,运用乘法结合律进行简算;
(3)
,把除数转化为乘它的倒数,再运用乘法分配律进行简算;(4)2.5+2.8+2.2+6.5.运用加法的交换律和结合律进行简算.
点评:此题考查的目的是熟练地运用运算定律对小数、分数四则混合运算进行简便计算.