the answer is -$97 for sure.
% a4 a9 h. a2 p$ z- K" q3 Qtvb now,tvbnow,bttvbThink about it this way
L; O) Y9 ^( [公仔箱論壇1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
3 z+ E+ {4 r- m% A, j: X2) Now, the owner discovered that the 100 bucks is fake. You can think this as a lost of $100. therefore the overall gain is $3-$100 = -$97 |
發表於 2007-5-16 03:12 AM
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發表於 2007-5-19 03:21 PM
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發表於 2007-5-21 03:49 AM
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