都说中国人数学好，看来未必

来源: 于 2010-11-06 21:21:59 [旧帖] [给我悄悄话] 本文已被阅读：次

: 1 - [(1 - a) * (1 - b)]

(1) 1 - [(1 - 60%) * ( 1 - 70%)] = 1 - 30% * 40% = 88%

(2) 1 - [(1- 50%) * (1 -100%)] = 1 - 50% * 0 = 100%