Efficiently Solve Difficult Math Problems

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Homework Help Overview

The discussion revolves around a math problem related to calculating average speed over different segments of a trip. The original poster expresses difficulty in finding a straightforward solution after attempting to calculate the average speed explicitly.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss calculating the time for each segment of the trip and question the method of determining the average speed. There are hints provided regarding the total trip time and segment times, and some participants explore whether a specific calculation method is appropriate.

Discussion Status

The discussion includes hints and attempts to clarify the approach to the problem. Some participants confirm the correctness of the calculations presented, indicating a productive exchange of ideas, though no consensus on a complete solution has been reached.

Contextual Notes

There is an indication that the original poster struggled with the problem despite it appearing simple at first, suggesting potential assumptions about the problem's complexity.

ehrenfest
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Homework Statement


What is the best way to do this problem? It looked easy but when I the solution just wasn't clicking for me. I tried to calculated the average speed of the last 20 miles explicitly and it took me a really long time and I had to crudely approximate the answer...I am pretty sure there is a simple way to do this.


Homework Equations





The Attempt at a Solution

 

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Hint: Figure out the time it takes for the total trip and each segment.
 
Doc Al said:
Hint: Figure out the time it takes for the total trip and each segment.

That's pretty much what I did. The first 30 miles take 3/4 hr and the last 20 miles take 13/36 hr. So then I just need to figure out whether 20*36/13 is greater than 45 by long division, right?
 
ehrenfest said:
That's pretty much what I did. The first 30 miles take 3/4 hr and the last 20 miles take 13/36 hr. So then I just need to figure out whether 20*36/13 is greater than 45 by long division, right?

That's correct.
 

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