the answer is -$97 for sure. TVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。5 W7 Z6 e; j0 G$ u
Think about it this way # S4 d! `3 d. q& T2 ~+ E% L" n
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)9 ]& Y4 T2 o# v4 f2 \+ W) f+ r
2) Now, the owner discovered that the 100 bucks is fake. You can think this as a lost of $100. therefore the overall gain is $3-$100 = -$97 |
發表於 2007-5-16 03:12 AM
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發表於 2007-5-19 03:21 PM
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發表於 2007-5-21 03:49 AM
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