SOLUTION: Christopher ran m miles at r miles per hour and arrived on time. Then the distance was increased 7 miles. How fast did he have to run to travel the new distance in the same amount

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Question 1091242: Christopher ran m miles at r miles per hour and arrived on time. Then the distance was increased 7 miles. How fast did he have to run to travel the new distance in the same amount of time?
Found 2 solutions by ankor@dixie-net.com, MathTherapy:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Christopher ran m miles at r miles per hour and arrived on time.
time = m%2Fr
Then the distance was increased 7 miles.
(m+7)
How fast did he have to run to travel the new distance in the same amount of time?
let s = the increase in speed required to do this
%28%28m%2B7%29%29%2F%28%28r%2Bs%29%29 = m%2Fr
cross multiply
m(r+s) = r(m+7)
distribute
mr + ms = mr + 7r
subtract mr from both sides
ms = 7r
s = %287r%29%2Fm mph the increase in speed
"How fast to run to travel the new distance in the same amount of time?
r + %287r%29%2Fm mph is the required speed

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Christopher ran m miles at r miles per hour and arrived on time. Then the distance was increased 7 miles. How fast did he have to run to travel the new distance in the same amount of time?
Time = m%2Fr

New distance: m + 7

Speed at which to travel: