the answer is -$97 for sure. ; E9 i8 q" q& I$ Q; ]: ~
Think about it this way 5 e. K. Y2 c% p! X. H
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)tvb now,tvbnow,bttvb: |. g$ Q: \1 j$ L, X: C' ^* a
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
| 
發表於 2007-5-19 03:21 PM
| 
發表於 2007-5-21 03:49 AM
| 