Distance Problem 3 - Uniform Motion rt=d
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
More free YouTube videos by Julie Harland are organized at http://yourmathgal.com
- How do you solve uniform motion problems?
- How do you solve equations using the formula rate * time = distance?
- How can you draw and use pictures to solve word problems using the formula d = rt?
- How can you come up with an equation to solve a uniform motion problem?
- How can you use a chart to solve a uniform motion problem?
- How can you check your solutions to a uniform motion problem?
- On a 555-mile, 5-hour trip on the Autobahn, a car drove two speeds. If the average speed of the car was 105 mph on the first part and 105 mph on the second part, how long did the car drive at each speed?
- If you know the rate of two parts of a car trip, how do you write an expression for the time and distance of the car?
-
Staff Review
This is a classic problem in which a car drives at two different speeds, and you have to find how long it traveled at each speed given the total distance and total time of the trip. This is a great lesson explained and solved using equations found from a chart and sketch. -
