SOLUTION: The total travel time for a family to reach a campsite is 2 hours. They drive 81 miles and hike 2 miles.
If they drive 50 mph faster than they hike, what is their average driving
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If they drive 50 mph faster than they hike, what is their average driving
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Question 910302: The total travel time for a family to reach a campsite is 2 hours. They drive 81 miles and hike 2 miles.
If they drive 50 mph faster than they hike, what is their average driving speed?
You can put this solution on YOUR website! The total travel time for a family to reach a campsite is 2 hours. They drive 81 miles and hike 2 miles.
If they drive 50 mph faster than they hike, what is their average driving speed?
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d = r*t
t = d/r
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r = hiking speed
2/r + 81/(r+50) = 2
2(r+50) + 81r = 2r*(r+50) = 2r^2 + 100r
2r + 100 + 81r = 2r^2 + 100r
2r^2 + 17r - 100 = 0
(r - 4)*(2r + 25) = 0 (Ignore the negative solution)
r = 4 mi/hr
Driving speed = 54 mi/hr
