the answer is -$97 for sure.
; P* B9 g: p" l. p& y/ b: w8 m, IThink about it this way
9 b v) }4 l9 a1 h( i, A0 V5 j公仔箱論壇1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
- Q5 B2 {& L* r* u% z8 ?5.39.217.772) 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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