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采用灵活、简捷的方法计算(1)95.6×19-95.6×9(2)(30+514)÷15(3)4-1÷3-13×8(4)18920÷9(5)15×7.5+(1+15)×3(6)3.2×1

题目详情
采用灵活、简捷的方法计算
(1)95.6×19-95.6×9 (2)(30+
5
14
)÷15
(3)4-1÷3-
1
3
×8
(4)18
9
20
÷9
(5)
1
5
×7.5+(1+
1
5
)×3
(6)3.2×12.5.
▼优质解答
答案和解析
(1)95.6×19-95.6×9,
=95.6×(19-9),
=95.6×10,
=956;

(2)(30+
5
14
)÷15,
=(30+
5
14
)×
1
15

=30×
1
15
+
5
14
×
1
15

=2+
1
42

=2
1
42


(3)4-1÷3-
1
3
×8,
=4-
1
3
-
8
3

=4-(
1
3
+
8
3
),
=4-3,
=1;

(4)18
9
20
÷9,
=18
9
20
×
1
9

=(18+
9
20
)×
1
9

=18×
1
9
+
9
20
×
1
9

=2+
1
20

=2
1
20


(5)
1
5
×7.5+(1+
1
5
)×3,
=
1
5
×7.5+
6
5
×3,
=1.5+3.6,
=5.1;

(6)3.2×12.5,
=0.4×8×12.5,
=0.4×(8×12.5),
=0.4×100,
=40.