题目内容
| 下面各题,怎样简便就怎样算 | |
| ( |
解:(1)
+
×
,
=
+
,
=
;
(2)
×
-
,
=
-
,
=
;
(3)
×
×
=
;
(4)
×
×17=5;
(5)
×
×
=
;
(6)
×
+
×
,
=
×(
+
),
=
×1,
=
;
(7)
×86,
=
×(85+1),
=
×85+
,
=3
;
(8)(
+
)×54,
=
×54+
×54,
=42+10,
=52.
分析:(1)先算乘法,再算加法;
(2)先算乘法,再算减法;
(3)(4)(5)约分计算;
(6)(8)运用乘法分配律简算;
(7)把86看作(85+1),运用乘法分配律简算.
点评:此题考查了四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律简便计算.
=
=
(2)
=
=
(3)
(4)
(5)
(6)
=
=
=
(7)
=
=
=3
(8)(
=
=42+10,
=52.
分析:(1)先算乘法,再算加法;
(2)先算乘法,再算减法;
(3)(4)(5)约分计算;
(6)(8)运用乘法分配律简算;
(7)把86看作(85+1),运用乘法分配律简算.
点评:此题考查了四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算定律简便计算.
练习册系列答案
相关题目