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| Question 102480:  It takes 1 hour longer to fly to St. Paul at 200 mi/h than it does to return at 250 mi/h. How far away is St. Paul?
 Answer by mjgulinello(10)
      (Show Source): 
You can put this solution on YOUR website! Let t = the time in hours that it takes to fly to St. Paul at 250mph. Since it takes 1 hour longer to fly there at 200mph, this will = t+1.
 We know the distance to and from St. Paul is the same, so we can represent this distance two ways:
 Distance = speed * time
 D = 250t
 and
 D = 200(t+1)
 Since the two distances are equal, we can now plug the first formula into the second one and get an equation with one variable.
 250t = 200(t+1)
 First use the distributive property on the right side of the equation.
 250t = 200t + 200
 Subtract 200t from each side of the equation.
 50t = 200
 Divide each side of the equation by 50.
 t = 4
 Now we know the time it takes to travel to St. Paul at 250mph is 4 hours.
 Next, we plug that into the equation for distance.
 D = 250t
 D = 250 * 4
 D = 1000
 St. Paul is 1000 miles away.
 We can check to make sure we got the right answer by using our second equation for distance.
 D = 200(t+1)
 D = 200 * (4+1)
 D = 200 * 5
 D = 1000
 Our answer checks out. That's all for this problem.
 
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