the answer is -$97 for sure.
6 U( R* j8 }- h$ {Think about it this way ! U$ L) S1 |' u) h9 Q% @2 \2 `
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
: y0 J* L! k, c4 Z# X7 w7 L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
| 
發表於 2007-5-19 03:21 PM
| 
發表於 2007-5-21 03:49 AM
| 