原帖由 prozzy 於 2007-5-18 23:05 發表。 
% q8 Y9 j/ r- X' w+ y# O7 J4 ~5.39.217.76the answer is -$97 for sure.
$ F B8 n, c* \1 y$ W5 ?3 ctvb now,tvbnow,bttvbThink about it this way
" Q4 D w% g$ I# @8 m; @$ F$ A5.39.217.761) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
+ X+ ^7 M& ~" ]$ p1 U$ O2) Now, the owner discovered that the 100 bucks is fake. You can th ... & }# [ T) t% [/ ^7 U; @; ]( I
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1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong& G+ Y( p% J3 d/ t8 Z; C
tvb now,tvbnow,bttvb% S, ~+ G; o3 b2 [
think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.
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4 q- C- p+ P" x9 o$ ^: Y6 Ntvb now,tvbnow,bttvbI know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |