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能用简便方法计算的用简便方法计算.

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能用简便方法计算的用简便方法计算.
25×1.25×32 
(3.75+4.1+2.15)×9.8
5400-2940÷28×27
(20.2×0.4+7.88)÷4.2
4
5
+
1
4
(1)25×1.25×32,
=(25×4)×(1.25×8),
=100×10,
=1000;
(2)(3.75+4.1+2.15)×9.8,
=10×9.8,
=98;
(3)5400-2940÷28×27,
=5400-105×27,
=5400-2835,
=2565;
(4)(20.2×0.4+7.88)÷4.2,
=(8.08+7.88)÷4.2,
=15.96÷4.2,
=3.8;
(5)(
4
5+
1
4)÷
7
3+
7
10,
=
21
20×
3
7+
7
10,
=
9
20+
14
20,
=
23
20,
=1
3
20;
(6)10÷[
8
3-(
5
13÷
5
26+
2
5)],
=10÷[
8
3-(
5
13×
26
5+
2
5)],
=10÷[
8
3-(2+
2
5)],
=10÷[
8
3-
12
5],
=10÷[
40
15-
36
15],
=10÷
4
15,
=10×
15
4,
=
75
2,
=37
1
2.