cost 15 to make the shoes, gave the boy 29 for change, and need 29 more to pay back the nieghborhood, so 15+29+29= 73. simple ,math problem. much easier than calculus~
: O! d( P2 M8 D9 d. o9 a公仔箱論壇tvb now,tvbnow,bttvb% h# [3 K `) [, l/ W8 z; Y
[ 本帖最後由 carsonchan 於 2009-2-15 04:18 PM 編輯 ] |