Harry's speed on the freeway is 67 miles per hour
Time Harry drove on freeway = 3 hours
Time Harry drove on country road = 6 hours
Total distance covered by him = 483 miles
Let his speed be x miles per hour
Formula to be used:
Speed*Time = Distance
Therefore, the distance covered by him on the freeway = 3x -----(1)
Distance covered by him on country road = 6(x - 20)------(2)
Formulating the question using (1) and (2)
3x + 6(x-20) = 483
3x + 6x - 120 = 483
9x = 603
x = 67 miles per hour
So, his speed on the freeway is 67 miles per hour and on the country road it is 47 miles per hour
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