Increasing speed by 5 mph saves 10 mins?

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To determine the distance and speeds involved when increasing speed by 5 mph saves 10 minutes, two equations are established based on the relationship between speed, time, and distance. The first equation represents the initial trip, while the second accounts for the increased speed and reduced time. By substituting the known variables, the equations can be set equal to each other, leading to a solvable format. The discussion emphasizes the importance of correctly manipulating these equations to find the desired values. Ultimately, the problem illustrates the mathematical principles governing speed and time in travel scenarios.
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If a person drives the same distance twice, and saves 10 mins by driving 5mph more the second time, what is the distance and the speeds?
 
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Speed * time = distance.

Set up two equations -- one for each trip -- and notice that the distances are equal. Thus, you can set the equations equal to each other, arriving at:

Speed1 * time1 = speed2 * time2.

You know that speed2 = speed1 + 5, and that time2 = time1 - 10.

Put these equations together and solve for distance...

- Warren
 
Can you work through it for me? I keep getting time1=10+2*speed1...
 
KingNothing said:
Can you work through it for me? I keep getting time1=10+2*speed1...
Write out your full two equations and show how you are trying to solve them.
 

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