SOLUTION: Maureen can run at a rate that is 3 miles per hour faster than her friend Hector's rate. While training for a mini marathon, Maureen gives Hector a half-hour head start and then be

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Question 704249: Maureen can run at a rate that is 3 miles per hour faster than her friend Hector's rate. While training for a mini marathon, Maureen gives Hector a half-hour head start and then begins chasing Hector on the same route. If Maureen passes Hector 9 miles from the starting point, how fast is each running?
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
Trying to put this into a rate-time-distance chart seemed confusing, but they both are at the same distance, 9 miles, when She catchs-up; meanwhile Hector has already gone %28his+rate%29%2F2 miles. Let t be the time needed for Maureen to match Hector's distance of 9 miles. Let Hector's speed be r.
When she passes Hector:
Maureen, %28r%2B3%29%2At=9
Hector, r%2At=9-%28r%2F2%29
Yes, during catchup time, Hector traveled less than 9 miles; the "t" is for catchup time.

Each equation transformable to solve for t.
Maureen: t=9%2F%28t%2B3%29
Hector: t=%289-%28r%2F2%29%29%2Fr
Equate the time, t:
9%2F%28r%2B3%29=%289-%28r%2F2%29%29%2Fr
.
with a bit of work,
r%5E2%2B3r-3%2A18=0
.
Solution to quadratic formula,,...
highlight%28r=6%29 miles per hour. That's Hector's speed.