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用递等式计算,能简算的要简算.3.72×3.5+6.28×3.575-38-5834-29+54+2913+(34-25)1517-(14-217)3.2×2.5×1.25.

题目详情
用递等式计算,能简算的要简算.
3.72×3.5+6.28×3.5
7
5
-
3
8
-
5
8
3
4
-
2
9
+
5
4
+
2
9
1
3
+(
3
4
-
2
5
15
17
-(
1
4
-
2
17
3.2×2.5×1.25.
▼优质解答
答案和解析
(1)3.72×3.5+6.28×3.5
=(3.72+6.28)×3.5
=10×3.5
=35;

(2)
7
5
-
3
8
-
5
8

=
7
5
-(
3
8
+
5
8

=
7
5
-1
=
2
5


(3)
3
4
-
2
9
+
5
4
+
2
9

=(
3
4
+
5
4
)+(
2
9
-
2
9

=2+0
=2;

(4)
1
3
+(
3
4
-
2
5

=
1
3
+
7
20

=
41
60


(5)
15
17
-(
1
4
-
2
17

=
15
17
-
1
4
+
2
17

=
15
17
+
2
17
-