the answer is -$97 for sure. 公仔箱論壇; @$ U4 ], j R! a8 l! ^& ]+ o
Think about it this way
" P; [& J# L |0 B* \8 e i3 u: r' 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。1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
8 E$ u4 `' b& N! a# m4 K# mTVBNOW 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 |