Increasing speed by 5 mph saves 10 mins?

In summary, the conversation discusses a scenario where a person drives the same distance twice and saves 10 minutes by driving 5mph faster the second time. The question asks for the distance and speeds involved. The solution involves setting up two equations for each trip and then setting them equal to each other. By substituting known values (speed2 = speed1 + 5, time2 = time1 - 10) and solving for distance, the solution can be derived.
  • #1
KingNothing
882
4
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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  • #2
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
 
  • #3
Can you work through it for me? I keep getting time1=10+2*speed1...
 
  • #4
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.
 

1. How does increasing speed by 5 mph save 10 minutes?

When you increase your speed by 5 mph, you are covering more distance in a shorter amount of time. This means that you will reach your destination faster, saving you 10 minutes compared to if you were driving at a slower speed.

2. Is increasing speed by 5 mph safe?

Increasing your speed by 5 mph may not seem like a significant change, but it can have a big impact on the safety of your driving. It is important to always follow the speed limit and consider the road conditions before increasing your speed.

3. Can increasing speed by 5 mph save more time on longer trips?

Yes, increasing your speed by 5 mph can save even more time on longer trips. The longer the distance, the more time you will save by driving at a faster speed. However, it is important to balance speed with safety and consider the potential risks of driving at a higher speed for a longer period of time.

4. Does increasing speed by 5 mph affect fuel efficiency?

Yes, increasing your speed by 5 mph can have a negative impact on fuel efficiency. As you drive faster, your car will use more fuel to maintain that speed. This means that while you may save time, you may end up spending more money on gas.

5. Are there other factors to consider when increasing speed by 5 mph?

Yes, there are other factors to consider when increasing your speed. These include road conditions, traffic, and the type of vehicle you are driving. It is important to always prioritize safety and follow the speed limit, even if it means taking a few extra minutes to reach your destination.

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