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递等式计算.(能简算的要简算)19.67-(1.67+229)-179(4-3.6×23)÷451118×27+117×5183.5×45+5.5×80%+0.86.4×1.25×2.52008÷2009×2010.

题目详情
递等式计算.(能简算的要简算)
19.67-(1.67+2
2
9
)-1 
7
9

(4-3.6×
2
3
)÷
4
5

11
18
×
2
7
+
11
7
×
5
18

3.5×
4
5
+5.5×80%+0.8
6.4×1.25×2.5
2008÷2009×2010.
▼优质解答
答案和解析

(1)19.67-(1.67+2
2
9
)-1
7
9

=19.67-1.67-2
2
9
-1
7
9

=(19.67-1.67)-(2
2
9
+1
7
9
),
=18-4,
=14;

(2)(4-3.6×
2
3
)÷
4
5

=(4-2.4)÷
4
5

=1.6÷
4
5

=2;

(3)
11
18
×
2
7
+
11
7
×
5
18

=
11
18
×
2
7
+
11
18
×
5
7

=
11
18
×(
2
7
+
5
7
),
=
11
18


(4)3.5×
4
5
+5.5×80%+0.8,
=3.5×0.8+5.5×0.8+0.8,
=(3.5+5.5+1)×0.8,
=10×0.8,
=8;

(5)6.4×1.25×2.5,
=(8×0.8)×1.25×2.5,
=(8×1.25)×(8×2.5),
=10×20,
=200;

(6)2008÷2009×2010,
=
2008
2009
×2010,
=
2008
2009
×(2009+1),
=
2008
2009
×2009+
2008
2009
×1,
=2008+
2008
2009

=2008
2008
2009