the answer is -$97 for sure. % ~5 g t4 Z, D5 q
Think about it this way 1 W& H4 [3 \% Y( z9 K. B+ k% a
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)$ ?/ Z! `( ^1 T; V2 Y
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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