题干

如某市现有织布厂35家,一共生产出100匹布。其中28家是手工劳动,一共生产了15匹布,他们生产1匹布的耗时分别是15家需要7小时,6家需要8小时,7家需要9小时;5家机械劳动,一共生产了60匹布,他们生产1匹布的耗时分别是3小时、3.5小时、4小时、4.5小时、5小时;2家是现代化劳动,一共生产了25匹布,他们生产1匹布的耗时分别是1小时和2小时。现在生产1匹布的社会必要劳动时间约是:

A:4小时

B:8小时

C:1.5小时

D:13.5小时

上一题 下一题 0.0难度 选择题 更新时间:2017-07-18 06:22:21

答案(点此获取答案解析)

A

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    Babbel – Learn Languages

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