| 0.125×32×25 | 128×99 | -(3.14+ ) | ( - )÷ +![]() |
+ + +![]() | + ÷![]() | 10.9-1.6-![]() | ÷( - ) |
2÷ ÷![]() | 6.5×99+6.5 | ( + + )×24 | 123×5.67+8.77×567 |
2- ×![]() | 2- ÷ -![]() | ÷(1- - ) | 49×![]() |
( + )×(1- ) | + + + . |
=(0.125×8)×(4×25),
=1×100,
=100;
(2)128×99,
=128×(100-1),
=128×100-128×1,
=12800-128,
=12672;
(3)
-(3.14+
),=10
-3.14-
,=10-3.14,
=6.86;
(4)(
-
)÷
+
,=

-
÷
+
,=2-
+
,=2;
(5)
+
+
+
,=(
+
)+(
+
),=
+
,=1
;(6)
+
÷
,=
+
,=1;
(7)10.9-1.6-
,=10.9-(1.6+3.4),
=10.9-5,
=5.9;
(8)
÷(
-
),=
÷
,=0.3;
(9)2÷
÷
,=2÷(
×
),=2÷
,=6;
(10)6.5×99+6.5,
=6.5×(99+1),
=6.5×100,
=650;
(11)(
+
+
)×24,=
×24+
×24+
×24,=12+8+4,
=20+4,
=24;
(12)123×5.67+8.77×567,
=5.67×(123+877),
=5.67×1000,
=5670;
(13)2-
×
,=2-0.3,
=1.7;
(14)2-
÷
-
,=2-(
+
),=2-2,
=0;
(15)
÷(1-
-
),=
÷(
),=
,=6;
(16)49×
,=(48+1)×
,=48×
+1×
,=5+
,=5
;(17)(
+
)×(1-
),=
×
,=
;(18)
+
+
+
,=(9+99+999+9999)+(
×4),=9++(99+1)+(999+1)+(9999+1),
=9+100+1000+10000,
=11109.
分析:(1)化32=8×4,再运用乘法结合律解答,
(2)(4)(10)(11)(12)(16)运用乘法分配律解答,
(3)(7)(14)依据减法的性质解答,
(5)运用加法交换律和结合律解答,
(6)(8)(13)(15)(17)依据四则运算计算方法解答,
(9)运用除法的性质解答,
(18)根据整数部分与整数部分,分数部分与分数部分相加解答.
点评:本题主要考查了学生运用四则运算计算方法,以及简便算法解决问题的能力