SOLUTION: A car travels 418 km in 6h. One hour of the trip is in the city, where its average speed is just half of what the car averaged on the turnpike for the rest of the trip. What was th
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-> SOLUTION: A car travels 418 km in 6h. One hour of the trip is in the city, where its average speed is just half of what the car averaged on the turnpike for the rest of the trip. What was th
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Question 145716: A car travels 418 km in 6h. One hour of the trip is in the city, where its average speed is just half of what the car averaged on the turnpike for the rest of the trip. What was the car's average city speed? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! A car travels 418 km in 6h. One hour of the trip is in the city, where its average speed is just half of what the car averaged on the turnpike for the rest of the trip. What was the car's average city speed?
:
Let s = city speed
then
2s = turnpike speed
:
The given information tells us, 1hr in the city, and 5 hrs on the turnpike
:
Write a distance equation: Dist = time * speed
:
City dist = turnpike dist = 418 mi
1x + 5(2s) = 418
1x + 10x = 418
x =
x = 38 mph in the city:
:
Check solution by finding the distance at each speed
1(38) = 38
5(76) =380
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total =418
