the answer is -$97 for sure. 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。+ ^+ y- Q7 t* B3 {- J, C
Think about it this way
8 U8 e+ r: f) i) f, I1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
2 [: O5 J% a- t) f9 etvb now,tvbnow,bttvb2) 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 |