原帖由 prozzy 於 2007-5-18 23:05 發表。 % i& K0 l$ w7 V( ]0 y
the answer is -$97 for sure.
' ^$ F& W" r8 d5 ^) }1 |5.39.217.76Think about it this way
G1 v: [) h2 d1 y2 I" L0 c1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)* W/ W) K O+ F
2) Now, the owner discovered that the 100 bucks is fake. You can th ... 0 W+ t+ U. F, U公仔箱論壇' {. N. ?2 q" @ F, E K0 K4 d2 F& i l& v
: F9 w( V' v# ktvb now,tvbnow,bttvb1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong6 v3 f% {- W- Z R. ?' m$ }" `
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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.5.39.217.76% I7 F5 n/ J4 M, F5 x( k! p) M
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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. |