the answer is -$97 for sure. $ y1 b0 x3 C3 E# K
Think about it this way ' O4 U( {- ?/ _$ c8 h
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
6 q! Q, F& C1 STVBNOW 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 |