原帖由 prozzy 於 2007-5-18 23:05 發表。 
: Y. O d5 i& s! I: X4 @" }tvb now,tvbnow,bttvbthe answer is -$97 for sure.
, H* B: v L/ i- F1 C b公仔箱論壇Think about it this way
+ E7 @& S! t) M# l3 o9 B! f. f5.39.217.761) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)tvb now,tvbnow,bttvb4 e$ p9 G( S2 Z. y0 z
2) Now, the owner discovered that the 100 bucks is fake. You can th ... 公仔箱論壇! w: ]- V0 M! K, b* p- p/ S( }0 Q" \
) W* _/ x" E: k % B) V7 {* ^0 c& E2 O
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3 Y( {7 f7 x! ]/ ?8 T
* G8 S+ F2 |( b7 U, Y
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.5.39.217.763 s" @: A1 y, J/ U& A+ H: n( f
' n7 e# d; u. `( |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. |