题目内容
| 计算下面各题,能简便计算的要用简便方法计算. 125×4÷10-20 |
7.1×15.4-5.4×7.1 | 1.25×32×2.5 | ||||||||||||||||||||
|
1÷[
|
(
|
(1)125×4÷10-20,
=500÷10-20,
=50-20,
=30;
(2)7.1×15.4-5.4×7.1,
=7.1×(15.4-5.4),
=7.1×10,
=71;
(3)1.25×32×2.5,
=1.25×8×4×2.5,
=(1.25×8)×(4×2.5),
=10×10,
=100;
(4)
×
+
÷
,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(5)1÷[
×(
-
)],
=1÷[
×
],
=1÷
,
=4;
(6)(
+
)×7+
,
=
×7+
×7+
,
=3+
+
,
=3+(
+
),
=3+5,
=8.
=500÷10-20,
=50-20,
=30;
(2)7.1×15.4-5.4×7.1,
=7.1×(15.4-5.4),
=7.1×10,
=71;
(3)1.25×32×2.5,
=1.25×8×4×2.5,
=(1.25×8)×(4×2.5),
=10×10,
=100;
(4)
| 5 |
| 7 |
| 3 |
| 4 |
| 2 |
| 7 |
| 4 |
| 3 |
=
| 5 |
| 7 |
| 3 |
| 4 |
| 2 |
| 7 |
| 3 |
| 4 |
=(
| 5 |
| 7 |
| 2 |
| 7 |
| 3 |
| 4 |
=1×
| 3 |
| 4 |
=
| 3 |
| 4 |
(5)1÷[
| 1 |
| 2 |
| 6 |
| 5 |
| 7 |
| 10 |
=1÷[
| 1 |
| 2 |
| 1 |
| 2 |
=1÷
| 1 |
| 4 |
=4;
(6)(
| 3 |
| 7 |
| 3 |
| 5 |
| 4 |
| 5 |
=
| 3 |
| 7 |
| 3 |
| 5 |
| 4 |
| 5 |
=3+
| 21 |
| 5 |
| 4 |
| 5 |
=3+(
| 21 |
| 5 |
| 4 |
| 5 |
=3+5,
=8.
练习册系列答案
相关题目