计算下面各题,能简便计算的要简便计算 3/7+1/4-13/28 4/5+(7/12+1/5)5-5/17-12/7 4/5-(1/6+3/10)
问题描述:
计算下面各题,能简便计算的要简便计算
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5-
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答
(1)
+3 7
-1 4
13 28
=
-19 28
13 28
=
;3 14
(2)
+(4 5
+7 12
)1 5
=(
+4 5
)+1 5
7 12
=1+
7 12
=1
;7 12
(3)5-
-5 17
12 7
=4
-12 17
12 7
=2
;118 119
(4)
-(4 5
+1 6
)3 10
=
-4 5
7 15
=
.1 3