原帖由 prozzy 於 2007-5-18 23:05 發表。 
8 i, u9 ~" G |+ B7 _tvb now,tvbnow,bttvbthe answer is -$97 for sure.
2 }7 x' }8 g% ~; D9 B( |- sThink about it this way
/ W" J' ]( E. H: T# S \tvb now,tvbnow,bttvb1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)0 `' C. |9 H4 V* k) p" l; H
2) Now, the owner discovered that the 100 bucks is fake. You can th ... ( p2 s6 ^5 t3 c. n5 M) k公仔箱論壇公仔箱論壇3 G+ o; R" W$ Q5 g6 X
5.39.217.77:8898+ h' i% C3 ?( v" t/ y
1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong5.39.217.77:8898+ v# ?3 h" M. r6 W! W
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think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.
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$ x8 w$ n' b* Q. |0 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。I know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |