喬大叔 wrote:7 + 4 = x - 2x = 13得知哥哥 13 歲...13 - 2 = y + 4y = 7故弟弟今年七歲... dodoyo wrote:錯答案在此 沒錯啊...弟弟今年七歲...這題的問題在於...題目一開始就跟你說弟弟今年七歲...卻要問你弟弟今年幾歲...還要運算式...所以...色夫便先算出哥哥年齡...再回算弟弟年紀...走個過場給你...答案其實就在題目中了...