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简便方法计算.(37+328)×7;35×63%+75×63%;5.2×14+1.8×0.25.

题目详情
简便方法计算.
(
3
7
+
3
28
)×7 ;
3
5
×63%+
7
5
×63% ;
5.2×
1
4
+1.8×0.25 .
▼优质解答
答案和解析
(1) (
3
7
+
3
28
)×7
=
3
7
×7+
3
28
×7
=3+
3
4

=3
3
4


(2)
3
5
×63%+
7
5
×63%
=(
3
5
+
7
5
)×63%
=2×0.63
=1.26;

(3) 5.2×
1
4
+1.8×0.25
=(5.2+1.8)×0.25
=7×0.25
=1.75.