the answer is -$97 for sure. tvb now,tvbnow,bttvb$ r- r, a2 y C I/ l6 K& }% U
Think about it this way , }! l# {, w; L* t, F$ X
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)tvb now,tvbnow,bttvb; B: N& B5 Z, Y; x2 O" m$ {" q% f
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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