即使按你的思路也应该是：1/3+2/31/3 +2/32/3*1/3 =19/27

来源: 方外居士于 2026-01-13 16:18:24 [旧帖] [给我悄悄话] 本文已被阅读：次

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即使按你的思路也应该是：1/3+2/3*1/3 +2/3*2/3*1/3 =19/27