the answer is -$97 for sure. 公仔箱論壇6 Y, g$ W8 C/ r4 ]
Think about it this way
0 X0 I9 E2 B! V, A, J2 w8 d4 Atvb now,tvbnow,bttvb1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
3 L- y" i& Q B$ w6 w# r2) 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
| 