问题 解答题
脱式计算
①2700×(506-499)÷900
②[1
1
8
+(0.65+
7
20
1
7
]×4.8.
答案

①2700×(506-499)÷900

=2700÷900×7,

=3×7,

=21;

②[1

1
8
+(0.65+
7
20
1
7
]×4.8,

=[1

1
8
+1÷
1
7
]×4.8,

=(1

1
8
+7)×4.8,

=

65
8
×4.8,

=39.

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