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(2011•盐池县模拟)脱式计算能用简便计算的要简算.(1)310+4.25+3.7+134(2)0.125×3.2×25(3)17×44+54×17(4)7.8÷〔32×(1-58)+3.6〕(5)56÷〔34×(79-13)〕

题目详情
(2011•盐池县模拟)脱式计算能用简便计算的要简算.
(1)
3
10
+4.25+3.7+1
3
4

(2)0.125×3.2×25
(3)
1
7
×44+54×
1
7

(4)7.8÷〔32×(1-
5
8
)+3.6〕
(5)
5
6
÷〔
3
4
×(
7
9
-
1
3
)〕
▼优质解答
答案和解析
(1)
3
10
+4.25+3.7+1
3
4

=
3
10
+3.7+4.25+1
3
4

=(
3
10
+3.7)+(4.25+1
3
4

=4+6
=10;

(2)0.125×3.2×25
=0.125×8×0.4×25
=(0.125×8)×(0.4×25)
=1×10
=10;

(3)
1
7
×44+54×
1
7

=
1
7
×(44+54)
=
1
7
×98
=14;

(4)7.8÷〔32×(1-
5
8
)+3.6〕
=7.8÷〔32×
3
8
+3.6〕
=7.8÷〔12+3.6〕
=7.8÷15.6
=0.5;

(5)
5
6
÷〔
3
4
×(
7
9
-
1
3
)〕
=
5
6
÷〔
3
4
×
4
9

=
5
6
÷
1
3

=2.5.