the answer is -$97 for sure. # v: d7 L& A$ S6 \
Think about it this way 5 @& h; C( p- L5 [0 r
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
/ i v: ^. ^, c* o/ d% ^1 }tvb now,tvbnow,bttvb2) 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
| 