拿根正態曲線（鍾型曲線）50-100 是A, 30-42.5是B，20-27.5是C。。。當然A 概率最高。

來源: 數字證於 2013-06-16 15:57:28 [舊帖] [給我悄悄話] 本文已被閱讀：次

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