| (1)4.05-2.86-0.14 | (2)75×60%+24× +0.6 |
(3)( - )×45 | (4) - ×( + ) |
| (5)10.2-(1.25+2.5)÷1.5 | (6)[2-( + )]÷1 . |
=4.05-(2.86+0.14),
=4.05-3,
=1.05;
(2)75×60%+24×
+0.6,=75×0.6+24×0.6+0.6,
=0.6×(75+24+1),
=0.6×100,
=60;
(3)(
-
)×45=
×45-
×45,=15-9,
=6;
(4)
-
×(
+
),=
-
×
,=
-
,=
;(5)10.2-(1.25+2.5)÷1.5,
=10.2-3.75÷1.5,
=10.2-2.5,
=7.7;
(6)[2-(
+
)]÷1
,=[2-
]÷1
,=
×
,=1.
分析:(1)运用减法的性质:连续减去两个数等于减去这两个数的和计算即可;
(2)(3)运用乘法分配律简算即可;
(4)(5)(6)运用运算顺序计算即可.
点评:计算注意运算顺序,合理利用运算定律使计算简便.