SOLUTION: A motorist drove 150 miles on country roads before driving on mountain roads. The rate of speed on the country roads was three times the rate on the mountain roads. The total tim

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Question 50777: A motorist drove 150 miles on country roads before driving on mountain roads. The rate of speed on the country roads was three times the rate on the mountain roads. The total time spent traveling the 200 miles was five hours. Find the rate of the motorist on the country roads.
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
Let the speed on the country road be 3x
x = mountain speed
50 miles were driven on mountain road
EQUATION:
150%2F3x%2B50%2Fx=5
150x%2B50%283x%29=5%28%283x%29%28x%29%29
300x=15x%5E2
x%5E2-20x=0
x=0 or x=20
20(3)=60
Hence, the speed on the country road was 60mph.
Paul.