the answer is -$97 for sure.
# n+ i y& O. p YThink about it this way 8 V2 ?. m" O4 x+ ]4 f
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)1 z4 u" O4 T; f% l" |
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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