the answer is -$97 for sure. 5.39.217.765 S R) r% X/ D
Think about it this way
6 [) H3 V: ]. U( y( E) z- u" d1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
# w' r& S( |3 Z' T) G6 k, ?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。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 |