SOLUTION: At 9 P.M. Lucy started to gallop her horse at 20 miles per hour to catch Edmund, who had a three hour head start. If Lucy was still 30 miles behind at 11P.M how fast was Edmund rid

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Question 281249: At 9 P.M. Lucy started to gallop her horse at 20 miles per hour to catch Edmund, who had a three hour head start. If Lucy was still 30 miles behind at 11P.M how fast was Edmund riding?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
At 9 P.M. Lucy started to gallop her horse at 20 miles per hour to catch Edmund, who had a three hour head start. If Lucy was still 30 miles behind at 11P.M how fast was Edmund riding?

           DISTANCE     RATE     TIME
Lucy         40          20       2
Edmond       5r           r       5

Lucy's distance = Edmond's distance - 30

             40 = 5r - 30
             70 = 5r
             14 = r

Checking:  Edmond started at 6PM. In the 5 hours up to 11PM, 
Edmond had traveled 14*5 or 70 miles.  Lucy started at 9PM.
In the 2 hours up to 11PM, Lucy had traveled 20*2 or 40 miles,
which puts her 30 miles behind Edmond.

Edwin