the answer is -$97 for sure.
1 N8 p' I! V+ DThink about it this way
|% Z r9 U6 r1 e: H1 R1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)tvb now,tvbnow,bttvb# \0 V+ e' P3 t$ }/ H
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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