the answer is -$97 for sure. , g* s$ r) I2 i0 b# K8 V0 T
Think about it this way
* g* i* K+ u2 ^6 `6 ^. {) W公仔箱論壇1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)3 d1 Z" x% q. V2 R9 B: | Y
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 2007-5-19 03:21 PM
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發表於 2007-5-21 03:49 AM
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