the answer is -$97 for sure. 5 `; U9 G7 ~! R2 { M* X
Think about it this way
f% a, j( k. [, Z0 h! U: b7 }" [6 l公仔箱論壇1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
! K8 d8 C& ?5 L, c! l8 J; BTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。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 |