SOLUTION: A car went a distance of 90 kilometers at a steady speed and returned along the same route at half that speed. The time for the round trip was 4 and a half hours. Find the two spee

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Question 879186: A car went a distance of 90 kilometers at a steady speed and returned along the same route at half that speed. The time for the round trip was 4 and a half hours. Find the two speeds
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi

Using total time for the trip in the Set Up

90mi%2Fr+%2B+90mi%2F%28r%2F2%29+=+8%2F2

90%2Fr+%2B+180%2Fr+=+8%2F2  |Multiplying thru by 2r so as all denominators = 1

    180 + 360 = 8r

         67.5mph = r

67.5mph and 38.75mph