SOLUTION: Lauren drove her car for 3 hours in a dust storm. When the skies cleared, she increased her speed by 30 miles per hour and drove for 4 more hours, completing her 295-mile trip. How

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Question 407389: Lauren drove her car for 3 hours in a dust storm. When the skies cleared, she increased her speed by 30 miles per hour and drove for 4 more hours, completing her 295-mile trip. How fast did she travel during the dust storm?
Answer by ankor@dixie-net.com(15652) About Me  (Show Source):
You can put this solution on YOUR website!
Lauren drove her car for 3 hours in a dust storm.
When the skies cleared, she increased her speed by 30 miles per hour and drove
for 4 more hours, completing her 295-mile trip.
How fast did she travel during the dust storm?
:
Let s = the slower speed
then
(s+30) = the faster speed
:
Write a distance equation, Dist = time * speed
:
Slow dist + fast dist = 295 mi
3s + 4(s+30) = 295
:
3s + 4s + 120 = 295
7s = 295 - 120
s = 175%2F7
s = 25 mph is the dust storm speed
:
:
Check the solution by finding the dist at each speed
3(25) + 4(55) =
75 + 220 = 295