the answer is -$97 for sure. TVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。8 P) u% j7 C7 b J* M* a
Think about it this way & f* V3 B, _( ?6 h$ n5 c$ c
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)TVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。; W- v$ l+ b& u3 z3 T, f
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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