bencake

題目誤導人~8 q% X3 |* b: b, z* O, b( z
owner 100
5 [  ^) V/ d1 p; _公仔箱論壇owner's son 20& u# L% m" @% m9 [2 d! w* T3 i9 X
each pay 405.39.217.77:8898  P5 x. B6 L* U. p; n; z
40*3 = 120  s! e2 p/ A. c4 k  y$ E
120(3 guys) - 20(owner's son) = 100 (owner)