the answer is -$97 for sure. 公仔箱論壇7 A# f3 H8 r* Y5 o
Think about it this way
. b; `, o7 U8 ~4 c$ e: M1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
. S5 }' V; B" n( L: `www1.tvboxnow.com2) 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 |