原帖由 prozzy 於 2007-5-18 23:05 發表。 
) E% i# J/ F5 }6 Ztvb now,tvbnow,bttvbthe answer is -$97 for sure.
& h) m+ y" R. c公仔箱論壇Think about it this way
! h9 W3 j' j; d2 c5.39.217.771) 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。' v) Z L% w/ T& W8 u' D0 d
2) Now, the owner discovered that the 100 bucks is fake. You can th ... $ p) i% W4 | t" u' M1 Y B公仔箱論壇" m. S5 [! d8 k
& a& \% p- b% t5 eTVBNOW 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。1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong
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: E) P$ r) v- w2 O8 `7 [9 l1 {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.
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- b+ s! p+ K2 Q6 a( _8 ftvb now,tvbnow,bttvbI know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |