the answer is -$97 for sure.
( d i/ m" J& qThink about it this way # t0 I$ D; H1 |4 ^5 J
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)" l# b$ a" v) T# ]% e
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 2007-5-21 03:49 AM
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