the answer is -$97 for sure.
& w# @5 L u$ R# G+ O7 Q5 Gtvb now,tvbnow,bttvbThink about it this way 公仔箱論壇+ c6 k, c. Q! Q+ Z' q
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)TVBNOW 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。: s: `0 \4 j' q) x- n& w! N
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 |