the answer is -$97 for sure.
: p H3 m$ @# g$ r' p( G4 N. M. f7 vThink about it this way
6 b L. M' V2 s: v; |+ t1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
) \4 Z6 u& H9 c; B0 R ]- j) }7 `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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