原帖由 prozzy 於 2007-5-18 23:05 發表。 
% V$ x8 S8 [# T* ltvb now,tvbnow,bttvbthe answer is -$97 for sure.
0 o2 ~7 _8 L) j1 D% }5.39.217.76Think about it this way 公仔箱論壇5 `' M3 O2 M) |; B) c
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
- [: D5 G! N A: F公仔箱論壇2) Now, the owner discovered that the 100 bucks is fake. You can th ... ) y) z% \* }1 k2 c& X( f: _
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公仔箱論壇* t3 B+ H# p( I
1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong7 w' Z; U+ |' s4 i+ z/ j1 U
0 k/ }0 ]" p8 V R; c* [2 ^" Tthink 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.
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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. |