SOLUTION: Bronwyn walks one lap of an oval at 2.5km/h and then jogs another 8 laps of the oval at 5km/h. If it takes her 30 minutes in total, how long in metres is each lap? I am guessing

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Question 263216: Bronwyn walks one lap of an oval at 2.5km/h and then jogs another 8 laps of the oval at 5km/h. If it takes her 30 minutes in total, how long in metres is each lap?
I am guessing that to work the answer out, simultaneous equations will need to be found.
In which case, I have figured that one of the simultaneous equations might be something like
5(8x) + 2.5(y) = 30 or something similiar, in which x stands for the distance covered when jogging, then multiplied by 8, the number of laps jogged, and then by 5, the speed at which it was jogged. And likewise for 2.5 and y.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Bronwyn walks one lap of an oval at 2.5km/h and then jogs another 8 laps of the oval at 5km/h. If it takes her 30 minutes in total, how long in metres is each lap?
:
We can do this with just one unknown, I would do it this way:
let x = length of one lap in meters
:
Write a time equation: time = dist/speed
Change 30 min to .5 hrs
:
time walking + time jogging = 30 min
x%2F2.5 + %288x%29%2F5 = .5
multiply by 5, clear the denominators, results:
2x + 8x = 5(.5)
10x = 2.5
x = 2.5%2F10
x = .25 km, length of 1 lap
which is
1000 * .25 = 250 meters
:
:
Check solution on calc
.25/2.5 + 8(.25)/5 =
.1 + .4 = .5 hrs