the answer is -$97 for sure.
2 [0 r: S3 C5 ~8 O) Q) E) @( I% i$ P# pTVBNOW 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。Think about it this way 0 {5 k+ L, R( y$ n5 e( M" b
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)tvb now,tvbnow,bttvb3 \7 k; \/ J- ?- f, ]/ h% s
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 2007-5-21 03:49 AM
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