原帖由 prozzy 於 2007-5-18 23:05 發表。 
+ M- x5 x$ B, J4 B. f: ^( qthe answer is -$97 for sure.
' D$ E3 [$ q7 h! Utvb now,tvbnow,bttvbThink about it this way 公仔箱論壇- S2 i- m# r' M, M! W- [2 Q7 v
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)5.39.217.76# x9 v- o( M3 g* }9 `& }
2) Now, the owner discovered that the 100 bucks is fake. You can th ... + L& s; H# N( a4 q8 Q4 r/ l% s) jtvb now,tvbnow,bttvb
: }& ]: F P% p5.39.217.76 公仔箱論壇2 }9 I7 L6 T0 d* p Q! i
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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think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.. n+ J6 H& ?1 ?0 L( I8 ]( \
7 k9 y5 E$ i$ V0 z公仔箱論壇I know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |