the answer is -$97 for sure.
4 ^/ c2 U0 f2 [8 S7 y" O6 ^: G公仔箱論壇Think about it this way 公仔箱論壇1 D' J, \, g- I3 \; R5 \* f
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18): g, y+ H8 B( n8 k! y [3 {
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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