SOLUTION: How long will it take someone running at 12 mph to catch up to someone walking at 5 mph with an hour and a half head start? I'm thinking that I can set up a system of equations

Algebra ->  Rate-of-work-word-problems -> SOLUTION: How long will it take someone running at 12 mph to catch up to someone walking at 5 mph with an hour and a half head start? I'm thinking that I can set up a system of equations      Log On


   



Question 548284: How long will it take someone running at 12 mph to catch up to someone walking at 5 mph with an hour and a half head start?
I'm thinking that I can set up a system of equations and figure it out from there, but I can't figure out how to set it up. help please!
Thank-you!

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+d%5B1%5D+=+r%2At+
+d%5B1%5D+=+5%2A1.5+
+d%5B1%5D+=+7.5+ mi
The 5 mi/hr walker has a 7.5 mi head start
Start a stopwatch when the 12 mi/hr runner starts
It will now take them both the same amount of time
until they meet. Call this time t
Runner's equation:
(1) +d+=+12t+
Walker's equation:
(2)
(2) +7t+=+7.5+
(2) +t+=+1.071+ hrs
+.071%2A60+=+4.26+
It will take the runner 1 hr and 4 min to catch walker
Really strange numbers, hope I got it right