SOLUTION: Harry drove for 5 hours on the​ freeway, then decreased his speed by 20 miles per hour and drove for 2 more hours on a country road. If his total trip was 4422 ​miles,

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Question 1104387: Harry drove for 5 hours on the​ freeway, then decreased his speed by 20 miles per hour and drove for 2 more hours on a country road. If his total trip was 4422 ​miles, then what was his speed on the​ freeway
Found 2 solutions by addingup, josgarithmetic:
Answer by addingup(3677) About Me  (Show Source):
You can put this solution on YOUR website!
he drove 4422 miles? That's a lot of miles!
Distance:
5 hours at speed x = 5x
2 hours at speed x-20 = 4422-2(x-20)
5x = 4422-2x-40
7x = 4382
distance at x-20: 4422-5x
5x+2(x-20) = 4422
5x+2x-40 = 4442
7x = 4382
x = 626 In order to drive 4422 at 5x + 2(x-20), he would have to drive the first 5 hours at 626 miles per hour. Is he driving a jet plane?

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
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Harry drove for 5 hours on the​ freeway, then decreased his speed by 20 miles per hour and drove for 2 more hours on a country road. If his total trip was 4422 ​miles, then what was his speed on the​ freeway
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FREEWAY         r          5
COUNTRY         r-20       2
TOTAL                      7             4422

Variable assigned and information tabulated according to problem description.
Fill in the missing pieces.
              SPEED      TIME        DISTANCE
FREEWAY         r          5         5r
COUNTRY         r-20       2         2(r-20)
TOTAL                      7          4422

Solve the equation highlight_green%285r%2B2%28r-20%29=4422%29.

You might get a strange value for r. The problem is not the best made-up exercise example.

(637 mph, for r; recheck your original problem description.)