the answer is -$97 for sure.
+ m) @& C. N9 ]5 n3 Q; D# wThink about it this way 6 W4 S0 _) t: N
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)公仔箱論壇9 z9 J; }& B# f' `' @$ e, M6 i" V
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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