the answer is -$97 for sure. 3 s& a% ^" \# BThink about it this way 公仔箱論壇& ^% ~, v% L) i
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)os.tvboxnow.com% |; J* B) G1 n$ }
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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