SOLUTION: The time t required to drive a fixed distance varies inversely as the speed r. It takes 5 hrs at a speed of 80 km/h to drive a fixed distance. How long will it take to drive the sa

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Question 585398: The time t required to drive a fixed distance varies inversely as the speed r. It takes 5 hrs at a speed of 80 km/h to drive a fixed distance. How long will it take to drive the same distance at a speed of 70 km/h?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The time t required to drive a fixed distance varies inversely as the speed r.
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t = k/r
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Solve for "k" using "It takes 5 hrs at a speed of 80 km/h to drive a fixed distance".
5 = k/80
k = 400
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Equation:
t = 400/r
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How long will it take to drive the same distance at a speed of 70 km/h?
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t(70) = 400/70 = 5.71 hours
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Cheers,
Stan H.
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