考點:運算定律與簡便運算,小數(shù)四則混合運算,整數(shù)、分數(shù)、小數(shù)、百分數(shù)四則混合運算
專題:運算順序及法則,運算定律及簡算
分析:(1)先除以0.8,再乘上0.8,再根據(jù)除法的性質(zhì)進行簡算;
(2)先把除法轉化為乘法,并把括號里的進行化簡,再利用乘法分配律簡算;
(3)利用減法的性質(zhì)簡算;
(4)先把除法轉化為乘法,分數(shù)化為小數(shù),再利用乘法分配律以及減法的性質(zhì)簡算;
(5)利用乘法分配律簡算.
解答:
解:(1)1.02÷1.25
=1.02÷1.25÷0.8×0.8
=1.02÷(1.25×0.8)×0.8
=1.02÷1×0.8
=1.02×0.8
=0.816;
(2)4.6×
+4.4÷1
+(1-0.1)
=4.6×
+4.4×
+
=(4.6+4.4+1)×
=10×
=9;
(3)5.87-(3.87-0.96)
=5.87-3.87+0.96
=2+0.96
=2.96;
(4)101÷
-11
=101×10.1-11.1
=101×10.1-10.1-1
=(101-1)×10.1-1
=100×10.1-1
=1010-1
=1009;
(5)(
+
)×29×23
=
×29×23+
×29×23
=2×23+3×29
=46+87
=133.
點評:本題考查了運算定律與簡便運算,四則混合運算.注意運算順序和運算法則,靈活運用所學的運算定律簡便計算.