Question 99972
The problem says she went twice as far jogging as she did walking so:
2*5*t=8*(2.25-t), where t is for time. Solving this equation tells you 
how long she did both, then substitute back in for each speed to get total distance.
so 10t=18-8t, and 18t=18, so t=1 hour.
so (5*1)+(8*1.25)= total distance traveled = 15 miles which is the length of the walkathon.