解:(1)(7.6-1
+80%)÷(1-30%),
=(6.2+0.8)÷(1-0.3),
=7÷0.7,
=10;
(2)75%×0.375+1.625×
-0.75,
=0.75×(0.375+1.625-1),
=0.75×1,
=0.75;
(3)24-4.62-5.38,
=24-(4.62+5.38),
=24-10,
=14;
(4)1.25×2.5×32,
=1.25×2.5×4×8,
=(1.25×8)×(2.5×4),
=10×10,
=100;
(5)[
-(25%+
)]÷10%,
=[
-0.6]÷10%,
=0.15÷0.1,
=1.5;
(6)
÷[(
-
)×
],
=
÷[
×
],
=
÷
,
=5.
分析:(1)先分別計(jì)算兩個(gè)小括號(hào)里面的加減法,再算括號(hào)外的除法;
(2)運(yùn)用乘法分配律簡算;
(3)根據(jù)減法的性質(zhì)簡算;
(4)先把32分解成4×8,再運(yùn)用乘法結(jié)合律簡算;
(5)先算小括號(hào)里面的加法,再算中括號(hào)里面的減法,最后算括號(hào)外的除法;
(6)先算小括號(hào)里面的減法,再算中括號(hào)里面的乘法,最后算括號(hào)外的除法.
點(diǎn)評(píng):此題主要考查分?jǐn)?shù)、整數(shù)、小數(shù)的四則混合運(yùn)算的運(yùn)算順序和應(yīng)用運(yùn)算定律進(jìn)行簡便計(jì)算.