In this lesson, we learn how to solve a uniform motion distance problem using the rt=d formula. The problem involves a 555-mile, 5-hour trip driven at two different speeds. By breaking the trip into two parts, one moving at 105 mph and the other at 115 mph, we are able to solve for the time and distance of each part. The solution is 105 mph for 2 hours and 115 mph for 3 hours.
Solves this word problem using rt=d formula: A 555-mile, 5-hour trip on the Autobahn was driven at two speeds. The average speed of the car was 105 mph on the first part of the trip, and the average speed was 115 mph for the second part. How long did the car drive at each speed?
Answer: 105 mph for 2 hours and 115 mph for 3 hours
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