SOLUTION: Suppose you travel a total of 100 miles. For the first mile, you were going at a speed of 1 mph. For the second mile, you were going at a speed of 2 mph. For the third mile, you we

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Question 457371: Suppose you travel a total of 100 miles. For the first mile, you were going at a speed of 1 mph. For the second mile, you were going at a speed of 2 mph. For the third mile, you were going at a speed of 3mph, and so on. What would be your average speed over the entire 100-mile trip?
Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
Your first mile would take 1 hour at 1 mph. Your second mile would take 1/2 hour.
Your third mile takes 1/3 hour, etc., etc.. Following this pattern is known as the harmonic series and the sum of the first 100 terms is 5.187. So you've traveled 100 miles over 5.187 hours, so your average speed was 100/5.187 or 19.28 mph..