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~5.39.217.77:8898. I" U# t( D; l6 n4 H3 ?, ^
5.39.217.77:88989 |* ?3 C2 I! N- v* H& L: F
[ 本帖最後由 carsonchan 於 2009-2-15 04:18 PM 編輯 ] |