小桶中装有浓度为20%的糖水1000克，每次加人80克浓度为50%的糖水。加到 ( )次时，将使桶中糖水浓度超过40%。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='31504' and id < 2524901 and id<>'2524901' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='31504' and id > 2524901 and id<>'2524901' order by id asc limit 5