Question 727590: Mandy drove slowly for 3 hours in a rain storm. When the skies cleared she increased her speed by 30 mph and drove 4 more hours, completing her 295 mile trip. How fast was she driving in the rain storm?
Answer by solver91311(24713)   (Show Source):
You can put this solution on YOUR website!
We know that distance equals rate times time. We know that the time during the rainstorm was 3 hours, but we don't know the distance or the rate. So all we can say is:
where  is the distance driven while it was raining and  is the speed driven during the rain.
The time after the rainstorm was 4 hours, and although we don't know the speed driven during these 4 hours, we do know that it was 30 miles per hour faster, hence:
)
where  was the distance driven when it was clear, and  , being 30 miles per hour faster than the speed when it was raining, is the speed when it was clear.
Then we know that the two distances when added together make 295 miles, in other words: 
Substituting the RHSs of the first two equations we get:
\ =\ 295)
Solve for
John
Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
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