解:(1)3780÷35+13×308,
=108+4004,
=4112;
(2)
÷[
×(
+10%)],
=
[
(
)],
=
[
],
=
,
=
30,
=7
;
(3)2.5×0.32×12.5,
=(2.5×0.4)×(0.8×12.5),
=1×10,
=10.
分析:(1)3780÷35+13×308,根據(jù)整數(shù)四則混合運(yùn)算的運(yùn)算順序按照整數(shù)四則運(yùn)算的計(jì)算法則進(jìn)行計(jì)算;
(2)
÷[
×(
+10%)],把百分?jǐn)?shù)化成分?jǐn)?shù),再根據(jù)分?jǐn)?shù)四則混合運(yùn)算的運(yùn)算順序按照分?jǐn)?shù)四則運(yùn)算的計(jì)算法則進(jìn)行計(jì)算;
(3)2.5×0.32×12.5,轉(zhuǎn)化為:0.25×0.4×0.8×12.5,再應(yīng)用乘法結(jié)合律進(jìn)行簡(jiǎn)算;
(4)
×3.2+7.8÷
-
,把除數(shù)轉(zhuǎn)化為乘它的倒數(shù),再運(yùn)用乘法分配律進(jìn)行簡(jiǎn)算.
點(diǎn)評(píng):此題主要考查整數(shù)、小數(shù)、分?jǐn)?shù)四則混合運(yùn)算,考查目的是使學(xué)生牢固掌握它們的運(yùn)算順序和計(jì)算法則,并且能夠靈活運(yùn)用運(yùn)算定律進(jìn)行簡(jiǎn)便計(jì)算.