题目内容
能简便的用简便方法计算
| (5.6-1.6÷2)×2.5 |
| ||||||||||
2001÷
|
|
(1)(5.6-1.6÷2)×2.5,
=(5.6-0.8)×2.5,
=4.8×2.5,
=1.2×4×2.5,
=1.2×(4×2.5),
=1.2×10,
=12;
(2)
×9-8÷
,
=
×9-8×
,
=
×(9-8),
=
×1,
=
;
(3)2001÷
,
=2001×
,
=2001×
,
=2001×(1+
),
=2001+
,
=2001+1
,
=2002
;
(4)
+
+
+…+
,
=
+
+
+…+
,
=(
+
+
+…+
)-(
+
+
+…+
),
=(
-
+
-
+
-
+…+
-
)-
×(
-
+
-
+
-
+…+
-
),
=(
-
)-
×(
-
),
=(
-
)×(1-
),
=
×
,
=
.
=(5.6-0.8)×2.5,
=4.8×2.5,
=1.2×4×2.5,
=1.2×(4×2.5),
=1.2×10,
=12;
(2)
| 8 |
| 17 |
| 17 |
| 8 |
=
| 8 |
| 17 |
| 8 |
| 17 |
=
| 8 |
| 17 |
=
| 8 |
| 17 |
=
| 8 |
| 17 |
(3)2001÷
| 1998 |
| 1999 |
=2001×
| 1999 |
| 1998 |
=2001×
| 1998+1 |
| 1998 |
=2001×(1+
| 1 |
| 1998 |
=2001+
| 2001 |
| 1998 |
=2001+1
| 1 |
| 666 |
=2002
| 1 |
| 666 |
(4)
| 2 |
| 2×5 |
| 2 |
| 5×8 |
| 2 |
| 8×11 |
| 2 |
| 1991×1994 |
=
| 3-1 |
| 2×5 |
| 3-1 |
| 5×8 |
| 3-1 |
| 8×11 |
| 3-1 |
| 1991×1994 |
=(
| 3 |
| 2×5 |
| 3 |
| 5×8 |
| 3 |
| 8×11 |
| 3 |
| 1991×1994 |
| 1 |
| 2×5 |
| 1 |
| 5×8 |
| 1 |
| 8×?11 |
| 1 |
| 1991×1994 |
=(
| 1 |
| 2 |
| 1 |
| 5 |
| 1 |
| 5 |
| 1 |
| 8 |
| 1 |
| 8 |
| 1 |
| 11 |
| 1 |
| 1991 |
| 1 |
| 1994 |
| 1 |
| 3 |
| 1 |
| 2 |
| 1 |
| 5 |
| 1 |
| 5 |
| 1 |
| 8 |
| 1 |
| 8 |
| 1 |
| 11 |
| 1 |
| 1991 |
| 1 |
| 1994 |
=(
| 1 |
| 2 |
| 1 |
| 1994 |
| 1 |
| 3 |
| 1 |
| 2 |
| 1 |
| 1994 |
=(
| 1 |
| 2 |
| 1 |
| 1994 |
| 1 |
| 3 |
=
| 996 |
| 1994 |
| 2 |
| 3 |
=
| 332 |
| 997 |
练习册系列答案
相关题目