原帖由 prozzy 於 2007-5-18 23:05 發表。 
9 R1 ]- O4 u/ F% \* Y# [8 k5.39.217.77the answer is -$97 for sure. + U J8 \, W6 R3 _8 |! H" `
Think about it this way
8 l8 f# r/ k" k5 `1 c' T5.39.217.771) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
; R7 G/ O" B% P& [2 u/ ~tvb now,tvbnow,bttvb2) Now, the owner discovered that the 100 bucks is fake. You can th ... 8 i" U/ z! W6 z2 i5.39.217.77公仔箱論壇% S# B* V5 r" u1 ]! S. g! `
TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。: a) M6 \* X$ _
1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong公仔箱論壇5 k( @1 }% P! |4 }
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think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.公仔箱論壇( a" m+ q( o6 X8 |. m0 W
9 T! G$ L" ~# 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. |