原帖由 prozzy 於 2007-5-18 23:05 發表。 : q6 g% |. x6 I% P: n. |: ]
the answer is -$97 for sure. 2 @3 O4 C# l# ?0 l7 A @/ N
Think about it this way
4 [9 n# f p+ n. U1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)& `$ C" `. a3 W$ Q; p5 _2 a
2) Now, the owner discovered that the 100 bucks is fake. You can th ... tvb now,tvbnow,bttvb% M- X* v' B/ N" z+ U ^
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公仔箱論壇: c7 r9 j/ y; A. H. I2 j
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/ D, L% g* y! y# Y e
5.39.217.76+ a7 u2 ?+ a+ K4 j- _6 P
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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3 L1 c1 ^2 x4 V9 Ktvb now,tvbnow,bttvbI know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |