21+50+15=86
, y1 k" S# s: j. y5.39.217.76why 86...
4 r, D/ E! `' v' | k: {becos he change 50 "small money" then giv bck to customer 29 and he keep the balance 21
# v/ p5 Y; z7 N6 v9 @ T9 m' y公仔箱論壇then he giv bck his fren 50
0 g& h5 t) @0 |and the shoes cost is 158 \0 }: Z5 v) k
4 d, |. y3 G' V" B# {# wso total he loss is 86...
$ u+ ?' n* D I9 C- F( y
% E' \% d- B! Z" \ J: T5 S5 L/ H7 l[ 本帖最後由 ooichse 於 2008-12-3 01:54 AM 編輯 ] |