Question 1197865
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Hi  
D = rt (Distance the same or equal  to and from)
 Question States:
  (v - 15mph)(7.5hr) =  (v + 15mph)(7hr)
          .5v = 14.5*15
            v = 435mph
Checking:  420mph*7.5h = 450mph*7h = 3150mi  Checks
Wish You the Best in your Studies.
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