the answer is -$97 for sure. 公仔箱論壇 @; s: N" e7 d0 p5 z6 O2 a
Think about it this way
6 y/ S4 g5 _! p8 G1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)! l7 H1 B' r6 C' K h
2) 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 2007-5-21 03:49 AM
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