爸爸，哥哥，妹妹，三人现在年龄的和是64岁，当爸爸的年龄是哥哥的3倍时，妹
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\u6240\u4ee5x-9=y\uff0c3x-9=34-y
3x-9=34-x+9\uff0cx=13
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爸爸年龄为34岁时 那么妹妹为9+y 哥哥为x+y 爸爸为3x+y
y为两次年龄之间的年龄差 因为年龄是一起长的~
再因为他的条件 哥哥为妹妹的两倍 既2(9+y) 爸爸则为34
可得 x+y=2(9+y) 3x+y=34
得出X=13 y=-5 既妹妹9岁时 哥哥13 爸爸39
64-9-13-39=3
故现在妹妹10岁 哥哥14 爸爸40
妹妹十三岁
绛旓細寰鐜板湪鐖哥埜40宀锛屽摜鍝12宀锛屽濡8宀併
绛旓細鍝ュ摜姣斿濡瑰ぇ4宀侊紝鐖哥埜姣斿濡瑰ぇ30宀併傛墍浠ワ紝鐜板湪濡瑰骞撮緞锛氾紙64-30-4锛/3=10宀侊紝鍝ュ摜14宀侊紝鐖哥埜40宀 甯屾湜瀵逛綘鏈夊府鍔﹡
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绛旓細鍥犳 鐖哥埜 鍝ュ摜 濡瑰 48 16 9 鈶 46 14 7 鈶 鍥犱负涓変汉鐨骞撮緞鍜屼负61 鎵浠 闅忎究鎶婂摢涓憼鎴栬呪憽 鐩稿姞 鍗 濡傛灉鎶娾憼鐩稿姞灏辨槸 48+16+9=73 61-73=-12 锛12骞冲潎鍒嗗埌姣忎釜浜虹殑骞撮緞涓婂氨鏄-4 鎵浠ュ氨鏄48-4绛変簬44 16-4=12 9-4=5 涔熷氨鏄槸璇寸埜鐖革細44锛屽摜鍝锛...
绛旓細鐖哥埜骞撮緞涓34宀佹椂 閭ｄ箞濡瑰涓9+y 鍝ュ摜涓簒+y 鐖哥埜涓3x+y y涓轰袱娆″勾榫勪箣闂寸殑骞撮緞宸 鍥犱负骞撮緞鏄竴璧烽暱鐨剘鍐嶅洜涓轰粬鐨勬潯浠 鍝ュ摜涓哄濡圭殑涓ゅ 鏃2(9+y) 鐖哥埜鍒欎负34 鍙緱 x+y=2(9+y) 3x+y=34 寰楀嚭X=13 y=-5 鏃㈠濡9宀佹椂 鍝ュ摜13 鐖哥埜39 64-9-13-39=3 鏁鐜板湪濡瑰10宀 鍝ュ摜14 鐖哥埜...
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