SOLUTION: Liz ran at a rate of 8 miles per hour, then walked at 3 miles per hour. If it took her an hour and a half to run/walk a distance of 9 miles, for how long was she running
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: Liz ran at a rate of 8 miles per hour, then walked at 3 miles per hour. If it took her an hour and a half to run/walk a distance of 9 miles, for how long was she running
Log On
Question 222943: Liz ran at a rate of 8 miles per hour, then walked at 3 miles per hour. If it took her an hour and a half to run/walk a distance of 9 miles, for how long was she running Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Liz ran at a rate of 8 miles per hour, then walked at 3 miles per hour.
If it took her an hour and a half to run/walk a distance of 9 miles, for how long was she running
:
Let t = time running
the total time was given as 1.5h, therefore:
(1.5-t) = time walking
:
Write a distance equation: dist = speed * time
run dist + walk dist = 9 mi
8t + 3(1.5 - t) = 9
8t + 4.5 - 3t = 9
8t - 3t = 9 - 4.5
5t = 4.5
t =
t = .9 hrs running .9(60) = 54 min
:
:
Check the total dist: (1.5 - .9 = .6 hr spent walking)
8(.9) + 3(.6) =
7.2 + 1.8 = 9 mi
