the answer is -$97 for sure.
' V* H3 m# g0 Q& ^8 p" R2 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。Think about it this way 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。, ~+ q2 v1 F8 d2 z0 z: j
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
; j' P% I8 d+ G& h2) 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 |