= | = | = | = |
= | 99×0.25+0.25= | = | 7.2÷100-0.72÷10= |
= | = |
,=1

,=
;(2)
,=0.875-0.75,
=0.125;
(3)
,=
×
,=
;(4)
,=
×8+
×8,=7+6,
=13;
(5)
,=(5
+4
)+3.42,=10+3.42,
=13.42;
(6)99×0.25+0.25,
=(99+1)×0.25,
=100×0.25,
=25;
(7)
,=5.73+(1
-1
),=5.73+0,
=5.73;
(8)7.2÷100-0.72÷10,
=0.072-0.072,
=0;
(9)
,=(

)×
,=1×
,=
;(10)
,=4.85-(
+3
),=4.85-4,
=0.85.
分析:前两题都化成相同的形式的数再计算;(4)(6)(9)用乘法分配律简算;(5)(7)运用加法结合律简算;(10)利用减去两个数等于减去这两个数的和简算;其余题目按照运算法则直接运算.
点评:运算定律是常用的简便运算的方法,记住这些运算定律并灵活运用.