原帖由 prozzy 於 2007-5-18 23:05 發表。 
$ V: _0 w+ `2 q5.39.217.76the answer is -$97 for sure.
# ~% M5 P% k! r: ^% W+ N3 T o公仔箱論壇Think about it this way , o) z+ |: I' {9 |( y2 A/ d7 ^
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
3 C2 V6 Z1 K$ _) d3 tTVBNOW 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。2) Now, the owner discovered that the 100 bucks is fake. You can th ... * n6 J" c6 l m9 a
5.39.217.767 {, n' @$ f# j1 Z' o; ?( z, f' J. S
4 r0 \" \/ \1 m k! a" z; ~tvb now,tvbnow,bttvb1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong
/ D1 K: s3 g1 b' [5 x公仔箱論壇 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。! q) L+ `0 Z' l* r+ _9 ?
think 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.6 E1 d3 s. k0 n, V
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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. |