SOLUTION: otis hikes up to the falls at 3 km/h and returns by the same route at 5 km/h. if the entire trip takes him 7.5 h, how far is it to the falls?

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Question 191391: otis hikes up to the falls at 3 km/h and returns by the same route at 5 km/h. if the entire trip takes him 7.5 h, how far is it to the falls?
Answer by orca(409) About Me  (Show Source):
You can put this solution on YOUR website!
Let x represent the distance between the starting point and the falls.
The time spent on the way to the falls is x/3.
The time spent on the way from the falls is x/5.
As the total time spent is 7.5 hours, we have
x%2F3%2Bx%2F5+=+7.5
Solving for x, we have
5x+%2B+3x+=+112.5 multiply both sides by 3x5.
8x+=+112.5
x = 14.0625 km