题目内容
计算下列各题,能简算的要简算
(
|
3-
|
|
19÷[(
|
分析:(1)根据乘法分配律进行计算;
(2)先算除法,再根据连减的性质进行计算;
(3)根据乘法分配律进行计算;
(4)先算加法,再算乘法,最后算除法.
(2)先算除法,再根据连减的性质进行计算;
(3)根据乘法分配律进行计算;
(4)先算加法,再算乘法,最后算除法.
解答:解:
(1)(
+
-
)×24,
=
×24+
×24-
×24,
=8+6-1,
=13;
(2)3-
÷
-
,
=3-
-
,
=3-(
+
),
=3-1,
=2;
(3)
×
+
÷7,
=
×
+
×
,
=(
+
)×
,
=1×
,
=
;
(4)19÷[(
+
)×
],
=19÷[
×
],
=19÷
,
=24.
(1)(
1 |
3 |
1 |
4 |
1 |
24 |
=
1 |
3 |
1 |
4 |
1 |
24 |
=8+6-1,
=13;
(2)3-
3 |
2 |
21 |
10 |
2 |
7 |
=3-
5 |
7 |
2 |
7 |
=3-(
5 |
7 |
2 |
7 |
=3-1,
=2;
(3)
3 |
4 |
1 |
7 |
1 |
4 |
=
3 |
4 |
1 |
7 |
1 |
4 |
1 |
7 |
=(
3 |
4 |
1 |
4 |
1 |
7 |
=1×
1 |
7 |
=
1 |
7 |
(4)19÷[(
1 |
5 |
3 |
4 |
5 |
6 |
=19÷[
19 |
20 |
5 |
6 |
=19÷
19 |
24 |
=24.
点评:考查了运算定律与简便运算,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律简便计算.
练习册系列答案
相关题目