the answer is -$97 for sure. . g$ {8 W4 D! { ~4 o7 \ N# I. ^; a6 h
Think about it this way 1 ?2 }3 k+ D6 x) }" M
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
% J, k+ d5 ]5 Z9 r$ [+ |& N公仔箱論壇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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