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# Averages part I

### #1

Posted 29 July 2013 - 04:18 PM

Examine the following two problems:

A fellow travels from city A to city B. For the first hour, he drove at the constant speed of 20 miles per hour. Then he (instantaneously) increased his speed and, for the next hour, kept it at 30 miles per hour. Find the average speed of the motion.

A fellow travels from city A to city B. The first half of the way, he drove at the constant speed of 20 miles per hour. Then he (instantaneously) increased his speed and traveled the remaining distance at 30 miles per hour. Find the average speed of the motion.

These two problems are often confused. Calculate the solutions of the two problems. What is the difference in value between the two questions?

### #2

Posted 29 July 2013 - 04:58 PM Best Answer

**Edited by gavinksong, 29 July 2013 - 04:58 PM.**

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