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计算下面各题(能简算的要简算).①4×0.8×2.5×12.5②215÷[1-(15+13)]③(2.8+3.85÷3.5)×4.6④6.5×1.83+0.17×6.5⑤(58+227)×8+1127⑥920÷[32×(0.4+45)].

题目详情
计算下面各题(能简算的要简算).
①4×0.8×2.5×12.5               
2
15
÷[1-(
1
5
+
1
3
)]
③(2.8+3.85÷3.5)×4.6          
④6.5×1.83+0.17×6.5 ⑤(
5
8
+
2
27
)×8+
11
27
              
9
20
÷[
3
2
×(0.4+
4
5
)].
▼优质解答
答案和解析
①4×0.8×2.5×12.5,
=(4×2.5)×(0.8×12.5),
=10×10,
=100;

2
15
÷[1-(
1
5
+
1
3
)],
=
2
15
÷[1-
8
15
],
=
2
15
÷
7
15

=
2
7



③(2.8+3.85÷3.5)×4.6,
=(2.8+1.1)×4.6,
=3.9×4.6,
=17.94;

④6.5×1.83+0.17×6.5,
=6.5×(1.83+0.17),
=6.5×2,
=13;

⑤(
5
8
+
2
27
)×8+
11
27

=
5
8
×8+
2
27
×8+
11
27

=5+
16
27
+
11
27

=2+(
16
27
+
11
27
),
=2+1,
=3;

9
20
÷[
3
2
×(0.4+
4
5
)],
=
9
20
÷[
3
2
×
6
5
],
=
9
20
÷
9
5

=
1
4