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~
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[ 本帖最後由 carsonchan 於 2009-2-15 04:18 PM 編輯 ] |
發表於 2009-2-15 04:12 PM
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