原帖由 prozzy 於 2007-5-18 23:05 發表。 
( X# x' G3 b+ o, F公仔箱論壇the answer is -$97 for sure.
( V8 G+ i. j" M8 }tvb now,tvbnow,bttvbThink about it this way 7 Y4 Q4 s1 |5 E9 w" c1 h5 v
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
2 P3 [4 A. C% S" g2) Now, the owner discovered that the 100 bucks is fake. You can th ... ' w! b, a m9 Q- ^8 z
5 I9 M3 G, r$ i$ S5 M5.39.217.77 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。4 I" K' _& e; [7 e- M& E2 l( y& `
1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrongtvb now,tvbnow,bttvb5 k. {: N7 @5 S# d
9 g3 A7 n/ h4 B) C3 _( S5.39.217.77think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.tvb now,tvbnow,bttvb: [/ Y h" s6 |% J8 |" e
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I know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |