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Places A and B are 100 km apart on a highway. One car starts from A and anotherfrom B at the same time. If the cars travel in the same direction at different speeds,they meet in 5 hours. If they travel towards each other, they meet in 1 hour.Whatare the speeds of the two cars? |
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Answer» Let the speed of car at A be x kmph and the speed of car at B be y kmph As per the question, 5x - 5y = 100 x - y = 20... (1) andx + y = 100... (2) Solving (1) and (2), we get, x = 60 and y = 40 Speed of the car at A = 60 kmph Speed of the car at B = 40 kmph Let the speeds of the cars be x km/hr and y km/hr Case 1: When the cars are going in the same direction Relative speed = x - yDistance = 100 km Time = 100 / (x - y) = 5 hrs x - y = 100 / 5x – y = 20 ------------- (1) Case 2: When the cars are going in the opposite direction Relative speed = x + y Time =100 / (x + y) = 1 hrs x + y = 100 ------------- (2) Solving the equations (1) and (2), we getx = 60 and y = 40 Hence the speeds of the cars are 60 km/hr and 40 km/hr. |
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