原帖由 prozzy 於 2007-5-18 23:05 發表。 + c# A: q+ |3 Q5 D+ j, O1 `
the answer is -$97 for sure.
9 U3 Z- O, B6 l+ r, n: E, N6 LThink about it this way 9 j2 h- h* ^3 C9 b
1) if the 100 bucks is not a fake one, the store owner will gain $3 ($21-$18)
' z2 y; t! ^5 a, r8 W/ D/ V" `2 q5.39.217.762) Now, the owner discovered that the 100 bucks is fake. You can th ... * N0 I" o, s1 x( K
% V. r2 Z# O& T: E# ttvb now,tvbnow,bttvb
) m# k8 ?9 G5 @& Y4 \* h1) very good, it the 100 bucks is real, your answer is correct, but it is fake, so your answer is wrong
7 R( h7 Y3 o' g+ S5 `, g4 p1 q tvb now,tvbnow,bttvb G. p. v% d/ D2 j$ ]
think about it, when the bill is fake, and he gave him $79 change back, that is -79 already, it means the 100 on his hand is equal to 0 (Zero), how did he makes profit when he got a fake bills, then he need to pay another real 100 dollars bill to his neighbor, that another -100, plus the product he lost, thats another 18 dollars, Do Not Even Mention the 3 dollars, there is no profit he can make when he got a fake bill.5 [8 m0 x" t0 Z6 j5 k: H) W4 M+ U
/ b, W; S! D( g3 u0 s' o8 P4 a公仔箱論壇I know the answer becoz it really happening to my friend in his store in real LIFE, it can not be wrong. |