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1、Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.一、行程问题基本数量关系路程=时间速度时间=路程/速度速度=路程/时间同时相向而行路程=时间速度之和同时同向而行路程=时间速度之差船在顺水中
2、的速度=船在静水中的速度+水流的速度船在逆水中的速度=船在静水中的速度-水流的速度Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.ABSV1V2S=T( + )V1V2Evaluation
3、 only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.AB同时同地同向在同一跑道进行比赛当男生第一次赶上女生时男生跑的路程-女生跑的路程=跑道的周长Evaluation only.Evaluation only.
4、Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.乙甲St同时异地追及问题乙的路程-甲的路程=甲乙之间的距离T ( - )=sV乙甲VEvaluation only.Evaluation only. Created with Aspose.Slides f
5、or .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.例1.某站有甲、乙两辆汽车, 若甲车先出发1后乙车出发, 则乙车出发后5追上甲车;若 甲车先开出30后乙车出发 ,则乙车出发4后乙车所走的 路程比甲车所走路程多10 求两车速度Evaluation only.Evaluation only. Created wi
6、th Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.若甲车先出发1后 乙车出发,则乙车出 发后5追上甲车解:设甲乙两车的速度分别为x Km/h、y Km/h根据题意,得x5x5y5y=6x若甲车先开出30后乙 车出发,则乙车出发4 后乙车所走的路程比甲车 所走路程多1030km
7、4x4y4y=4x+40解之得X=50 Y=6o答:甲乙两车的速度分别为 50km、60kmEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.例2.一列快车长230米,一列慢 车长220米,
8、若两车同向而行, 快车从追上慢车时开始到离开慢 车,需90秒钟;若两车相向而行 ,快车从与慢车相遇时到离开慢 车,只需18秒钟,问快车和慢车 的速度各是多少?Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose
9、 Pty Ltd.快车长230米,慢车长220 米,若两车同向而行,快 车从追上慢车时开始到离 开慢车,需90秒钟230m甲220m乙450m甲乙解:设快车、慢车的速 度分别为xm/s、ym/s 根据题意,得90(x-y)=450Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspos
10、e Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.若两车相向而行,快车 从与慢车相遇时到离开 慢车,只需18秒钟解:设快车、慢车的速 度分别为xm/s、ym/s 根据题意,得90(x-y)=450230m甲220m乙230m甲220m乙450m18s18(x+y)=450解之得X=15Y=10答:快车、慢车的速度分别为15m/s、10m/sEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with
11、Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.例3甲、乙两人在周长为400的 环形跑道上练跑,如果相向出发,每 隔2.5min相遇一次;如果同向出发 ,每隔10min相遇一次,假定两人速 度不变,且甲快乙慢,求甲、乙两人 的速度Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile
12、5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.甲、乙两人在周长为 400的环形跑道上练 跑,如果相向出发,每 隔2.5min相遇一次解:设甲乙两人的速度分 别为xm/min、ym/min 根据题意,得2.5(x+y)=400ABEvaluation only.Evaluation only. Created with Aspose.Slides for .NE
13、T 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.解:设甲乙两人的速度分 别为xm/min、ym/min 根据题意,得2.5(x+y)=400甲、乙两人在周长为400的环 形跑道上练跑,如果同向出发 ,每隔10min相遇一次甲 乙A10(X-Y)=400解之得X=100Y=60答:甲乙两人的速度分别 为100m/min、6
14、0m/minBEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.乙甲ABC环形跑道追及问题等 同于异地追及问题Evaluation only.Evaluation only. Created
15、 with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.例4.已知A、B两码头之间的距离为 240km,一艏船航行于A、B两码头之间, 顺流航行需4小时 ;逆流航行时需6小时, 求船在静水中的速度及水流的速度.Evaluation only.Evaluation only.
16、Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.练习.一辆汽车从甲地驶往乙地,途中要过一桥。用 相同时间,若车速每小时60千米,就能越过桥2千米 ;若车速每小时50千米,就差3千米才到桥。问甲地 与桥相距多远?用了多长时间?Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client P