一艘轮船从重庆到上海需5天，而从上海返回重庆要7天，那么一个木排从重庆顺水漂流到上海需要几天？ 一轮船从重庆到上海要5昼夜,而从上海到重庆要7昼夜,那么有一...
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\u6240\u4ee5\uff0c\uff081/5-1/7\uff09/2=1/35\u5c31\u662f\u6c34\u6d41\u7684\u901f\u5ea6\u3002
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\u7531\u9898\u610f\u5f97\uff1a\uff5b1/x+1/y=1/5
1/x-1/y=1/7
\u89e3\u5f97\uff1a\uff5bx=35/6
y=35
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绛旓細瑙ｈ杞埞鍦ㄩ潤姘翠腑鐨勯熷害涓簒/鏄煎,姘撮熶负y/鏄煎.(x+y)*5=(x-y)*7 x=6y (6y+y)/y =7y/y =7(鏄煎)
绛旓細宸茬煡锛杞埞閫熷害鏄疺锛孉涓嶣璺濈涓篠锛涗粠A鍒癇椤烘祦锛屾椂闂磘1鏄7澶╋紝閫嗘祦鏃堕棿t2=5澶╋紝姹傛按娴侀熷害浠嶢鍒癇鏃堕棿锛氳В锛氭按娴侀熷害vo S/锛圴+vo锛=5 S/锛圴-vo锛=7 鑱旂珛瑙ｅ緱V=6vo S=35vo t=S/vo=35澶
绛旓細鐢遍鎰忓拰宸茬煡锛屾湁锛氣憼锛歱/(m+n)=5锛涒憽锛歱/(m-n)=7锛涒憿锛歺=p/n銆傜敱鈶狅細m+n=p/5锛涚敱鈶★細m-n=p/7涓婁袱寮忕浉鍑忥紝寰楋細n+n=p/5-p/7锛屽嵆锛歯=p/35銆傚姝ゅ紡鍙樺舰锛屽緱锛歱/n=35銆傝屸憿涓猴細x=p/n锛屽彲瑙亁=p/n=35(澶)銆傜瓟锛氭湪鎺浠庨噸搴椤烘祦婕鍒颁笂娴烽渶瑕35澶┿
绛旓細姘撮 锛11/5-1/7锛壝2=1/35 闇瑕 1梅1/35=35鏄煎 璇峰ソ璇 ~鍦ㄥ彸涓婅鐐瑰嚮銆愯瘎浠枫戯紝鐒跺悗灏卞彲浠ラ夋嫨銆愭弧鎰忥紝闂宸茬粡瀹岀編瑙ｅ喅銆戜簡銆傚鏋滀綘璁ゅ彲鎴戠殑鍥炵瓟锛屾暚璇峰強鏃堕噰绾筹紝~浣犵殑閲囩撼鏄垜鍓嶈繘鐨勫姩鍔泘~~濡傝繕鏈夋柊鐨勯棶棰橈紝璇蜂笉瑕佽拷闂殑褰㈠紡鍙戦侊紝鍙﹀鍙戦棶棰樺苟鍚戞垜姹傚姪鎴栧湪杩介棶澶勫彂閫侀棶棰橀摼鎺ュ湴鍧锛...
绛旓細鑸閫熷害 V1 姘存祦閫烿2 涓婃捣鍒伴噸搴嗚矾绋 S : S/(V1+V2)=5 S/(V1-V2)=7 鍙互寰楀嚭 V1=6V2锛孲=35V2 褰撹埞閫熷害V1鍙樻垚2琚悗锛孷1=12V2锛屼粠涓婃捣鍒伴噸搴鏃堕棿涓 T=S/(12V2-V2)=35/11=3.2澶
绛旓細瑙ｏ細璁鑸鍦ㄩ潤姘翠腑x澶╁埌杈句笂娴凤紝鏈ㄦ帓y澶╁埌杈句笂娴枫傜敱棰樻剰寰楋細锝1/x+1/y=1/5 1/x-1/y=1/7 瑙ｅ緱锛氾經x=35/6 y=35 鈭存湪鎺35澶浠庨噸搴杈惧埌涓婃捣銆
绛旓細璁鑸鍦ㄩ潤姘碭澶浠庨噸搴嗗埌涓婃捣锛姘存祦鏄痀澶╁啿閲嶅簡娴佸埌涓婃捣 鎵浠ヨ埞鐨勯潤姘撮熷害涓1/X锛屾按娴侀熷害鏄1/Y 鍒欐湁鏂圭▼缁 1. 1/X+1/Y=1/5 2. 1/X-1/Y=1/7 瑙ｅ緱X=35/6 锛孻=35 鎵浠ヨ35鏄煎
绛旓細璁鑸鍦ㄩ潤姘碭澶浠庨噸搴嗗埌涓婃捣锛姘存祦鏄痀澶╁啿閲嶅簡娴佸埌涓婃捣 鎵浠ヨ埞鐨勯潤姘撮熷害涓1/X锛屾按娴侀熷害鏄1/Y 鍒欐湁鏂圭▼缁 1. 1/X+1/Y=1/5 2. 1/X-1/Y=1/7 瑙ｅ緱X=35/6 锛孻=35 鎵浠ヨ35鏄煎
绛旓細1梅锛1/5-1/7)*2=35
绛旓細35涓樇澶
