SOLUTION: My son had this problem on a test, can you help? Carla drove to the mountains, averaging 30 mph. Coming back by the same roads, she averaged 20 mph. The total driving time was

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Question 105765: My son had this problem on a test, can you help?
Carla drove to the mountains, averaging 30 mph. Coming back by the same roads, she averaged 20 mph. The total driving time was 5 hours. How far did she travel one way?
Found 2 solutions by kmcruz09, joLeeBee08:
Answer by kmcruz09(38) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the number of hours Carla traveled at 30mph
then 5 - x = number of hours she traveled at 20mph
The length of the roads will be either 30x or 20(5 - x) because d = rt.
We just equate the two expressions. We get:
30x+=+20%285-x%29
Then we solve for it.
30x=100-20x
50x=100
x=2
There, Carla traveled 30x+=+30%282%29+=+60 miles one way.
Thank you.
~kmcruz09~

Answer by joLeeBee08(3) About Me  (Show Source):
You can put this solution on YOUR website!
since we know that she traveled on the same path, the distance going to the mountain and the distance going home should be equal. Thus, the final equation shoul be: 30x = 20(5-x) >>> 30x = 100 - 20x >>> 50x = 100 >>> x = 2
* take note that x in this equation is the time it took her to go to the mountain and distance equals (speed)(time). Thus the answer is equal to 60m